# P-47 Movie (26 mb)



## Anonymous (Feb 23, 2005)

Enjoy!

=S=

Lunatic


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## evangilder (Feb 23, 2005)

WOW! RG, that was awesome! It's a large size, but well worth it. Thanks for posting that. 8) I know a WWII P-47 crew chief that is going to enjoy that.


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## the lancaster kicks ass (Feb 23, 2005)

when i get broadband i'll try an get that one.............


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## Udet (Feb 23, 2005)

RG:

That is an extremely interesting video!

What i find a bit strange though, is that on my guncamera footage collection i have the shot showing the Fw190 getting hit (the only one shown on this video). I wonder if it really was the guncamera of a P-47 from that specific fighter group.

I have detected many of these mistakes. For example, on one book I have, there is a series of photos from a guncamera showing "a Bf 110 getting pounded by a RAF interceptor during the Battle of Britain". Later on, i would discover it was in fact a P-38 getting shot down, when by a big coincidence i had the opportunity of seeing the actual guncamera recording! (The film was not of best quality, perhaps contributing to confuse the ones who made the book)

By the way, that particular shot shows how capable of absorbing damage the Fw190 was; play it many times and you´ll see it took three or four hits at very close range without showing any dramatic damage.


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## DaveB.inVa (Feb 23, 2005)

Lots of errors take place like that in books, movies and documentaries all the time. About 3/4 of the stuff you see on the History channel has errors like that in it. My big peeve is seeing whats supposed to be the Enola Gay and it has turrets and Hamilton Standard props.


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## polebrook351st (Feb 23, 2005)

Great film,would like to see some more.


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## Anonymous (Feb 23, 2005)

Udet said:


> RG:
> 
> That is an extremely interesting video!
> 
> What i find a bit strange though, is that on my guncamera footage collection i have the shot showing the Fw190 getting hit (the only one shown on this video). I wonder if it really was the guncamera of a P-47 from that specific fighter group.



I'm pretty sure the footage is from the P-47 group that had color cameras installed all over the plane to capture the action in 1945 just before the end of the war. It can be seen in full in one of "The Color of War" episodes, which show frequently on THC.

I agree that guncam footage is probably from earlier in the war, and may not even be from a P-47.

I have detected many of these mistakes. For example, on one book I have, there is a series of photos from a guncamera showing "a Bf 110 getting pounded by a RAF interceptor during the Battle of Britain". Later on, i would discover it was in fact a P-38 getting shot down, when by a big coincidence i had the opportunity of seeing the actual guncamera recording! (The film was not of best quality, perhaps contributing to confuse the ones who made the book)



Udet said:


> By the way, that particular shot shows how capable of absorbing damage the Fw190 was; play it many times and you´ll see it took three or four hits at very close range without showing any dramatic damage.



Well, as pointed out above by both of us, we really don't know when that footage was gathered or what kind of gun is hitting the plane, I highly suspect this is BoB footage from .303's. Also, it is very hard to assess damage from such images unless something major breaks off the target or it bursts into flames or explodes. Furthermore, I'm watching "Target Berlin" on the Military Channel right now and it has numerous clips of the wings popping off the FW's after only a fraction of a second of fire (perhaps 5 hits?). If you look at the wing structure of the FW below, it really is not built that tough - it has little redundancy and the axial runners are quite minimal in terms of structure (they're completely hollow twin "bows" which will loose integrity on almost any hit), as compared to those of the US fighters which are solid except for access holes. The FW wing was made to be rigid, but it really was not made to absorb a lot of damage.

The FW190 was certainly a tough plane when compared to the 109 or the Spitfire. But you really cannot compare it to the P-47 or F4U. The following cutaway's show the construction of several planes for comparison:

*FW190A-8*






*P-47C*





*F4U-1*





*P-51D*





*Spitfire Mk.I*





*A6M "Zero"*





As you can see, the structure of the FW is less than even the P-51, but more than either the Spit I or the Zero. Both the Corsair and the P-47 have tremendously more solid construction than the FW. Also, both use steel spars where the FW uses an aluminum spar, and sheet aluminum is "double thick" as compared to much thinner aluminum on the FW (which requires a special stepping spot to avoid damage to the wing).

Overall, not counting cooling system vulnerability (a big issue), I'd say the FW was much tougher than the Yak, Zero, or 109, a little tougher than the Spitfire (varies with model), perahaps a little tougher than the La5 or La7 (this could be debated), about the same as the P-51, and much less tough than the P-47, F4U, F6F, Typhoon, or Tempest.

In the end, the weight of a fighter usually gives a very good idea how tough it was.

=S=

Lunatic


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## CharlesBronson (Feb 23, 2005)

Some of the drastical failures in FW-190 that you named, probably was caused by the 50 cal API that punctured one or more 20 mm shell of the wings guns causing a internal deflagration of stored ammo. Also one explosion of unarmored oxigen bottles can cause a similar efect

This fenomen can be seen more often in FW-190 than BF-109 wich have a simplier wing estructure. 

One of his advantages is that Focke-Wulf have a much better pilot armor.


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## Anonymous (Feb 24, 2005)

CharlesBronson said:


> Some of the drastical failures in FW-190 that you named, probably was caused by the 50 cal API that punctured one or more 20 mm shell of the wings guns causing a internal deflagration of stored ammo. Also one explosion of unarmored oxigen bottles can cause a similar efect
> 
> This fenomen can be seen more often in FW-190 than BF-109 wich have a simplier wing estructure.
> 
> One of his advantages is that Focke-Wulf have a much better pilot armor.



It is certainly possible an ammo hit caused the wing to pop off, but there are also films of the tail poping off after taking just an instant of .50 fire (from 6 guns).

As for armor, the FW armor was "fair", but certianly not great.



> *FW190A-4*
> 
> 
> 
> ...



None of this armor can stop a .50 M8 API round at 90 degrees +/-30 degrees at ranges of 400+ meters, except possibly the headrest if the angle is near the limit (30 degrees). The A-8 had a little more armor, but only the 20mm plate on some variants would stop a .50 API round, and that armor only protected the pilot from the rear.

=S=

Lunatic


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## CharlesBronson (Feb 24, 2005)

I will aswer you in the Air-to-Air Weapon topic.


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## The Jug Rules! (Feb 24, 2005)

This just proves my point... THE JUG RULES!! \/ \/ \/


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## cheddar cheese (Feb 24, 2005)

Yeah it was a great plane 8)


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## Soren (Feb 24, 2005)

It was great plane because i toulk longer to shoot it down ?  

I would like to see how one would fair against a Bf109K-4


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## Soren (Feb 24, 2005)

It was a great ground attack aricraft though !


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## cheddar cheese (Feb 24, 2005)

Ah I think a P-47N would defeat a Kurfurst 8)


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## Anonymous (Feb 24, 2005)

Soren said:


> It was great plane because i toulk longer to shoot it down ?
> 
> I would like to see how one would fair against a Bf109K-4



As long as the P-47 kept the speed high and did not make a foolish goof, it should win that fight. It rolls much better, it's faster (a P-47D-RE-20 in combat trim or especially an M or N), it can maintain high speed much longer, it has a better gunsight, and better guns.

One on one it might be a relatively close fight, but in numbers, even with the 109's having few more, the P-47's would have the edge.

=S=

Lunatic


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## Soren (Feb 24, 2005)

The P-47's highest top speed was 433mph, the Bf109K-4 451mph   

Also the P-47 would bleed energy much quicker  And the Bf109K-4 would turn inside a P-47 any day at any speed 

I'd go for the Bf109K-4 !!


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## Anonymous (Feb 24, 2005)

Soren said:


> The P-47's highest top speed was 433mph, the Bf109K-4 451mph
> 
> Also the P-47 would bleed energy much quicker  And the Bf109K-4 would turn inside a P-47 any day at any speed
> 
> I'd go for the Bf109K-4 !!



No, the highest top speed for the P-47 was M version, which could manage about 475 mph. The N model could manage 467 mph. The Bf109K-4 was far from the best manuvering 109, and it would have a hard time turning inside the P-47 at high speed, and would probably be out-turned at high speed and high altitude. It would have no chance of rolling with it, at just about any speed or altitude. Factory specs for the P-47D-RE20 were about 430 mph level speed. But factory specs were for 2350 HP, where combat planes were tweaked to about 2700 HP.

The 109k could attain 451 mph for about 1 minute before overheating, the P-47M or N could sustain this speed for 11 minutes (the duration of Water injection). Furthermore, 109K top speed involves the use of GM1 SEP power, which was not very useable in combat situations (it was intended for fast climbing).

The 109K has about 10 seconds of cannon fire and about 45 seconds of 13mm fire, as opposed to about 40 seconds of .50 caliber fire from the P-47. The effective range of the 109K guns are about 100-150 meters for the MK108 and about 300-350 meters for the very weak MG131's, and its cannon is prone to jamming, especially when fired under G loads. The P-47 guns were effective to ranges well beyond 600 meters (using the K-14 gunsight), and were excellent for dogfighting.

The likelyhood of landing a MK108 round on a P-47 in mutually aware combat were quite poor. The MG131 13 mm rounds were so weak they'd have a hard time seriously hurting a P-47. On the otherhand, 8 x .50's would be easy to score with and would tear up a 109 in short order.

=S=

Lunatic


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## CharlesBronson (Feb 24, 2005)

Lunatic :

A little correction concerning the MG-131.

The gun fired at 840 rpm in sincro mode, this is 14 shot per second, with the 300 rounds belt Bf-109 K-4 have, give us 24,5 second of continuos fire.


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## Anonymous (Feb 24, 2005)

CharlesBronson said:


> Lunatic :
> 
> A little correction concerning the MG-131.
> 
> The gun fired at 840 rpm in sincro mode, this is 14 shot per second, with the 300 rounds belt Bf-109 K-4 have, give us 24,5 second of continuos fire.



Hmmm... I thought the 109K held 475 rpg. Perhaps that is the figure for the Dora9 and I messed up?

The thing about the MG131 is it had to fit, with little rework, where the MG17 fit. This meant it had to work off of a single mounting point (most HMG's require two), and be rather small. As a result it fires a medium velocity round of only about 34 grams, making it very weak for its caliber.

Thanks

=S=

Lunatic


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## Soren (Feb 25, 2005)

RG_Lunatic said:


> The MG131 13 mm rounds were so weak they'd have a hard time seriously hurting a P-47.



Haha !!  

Lunatic first of all the MG131 13mm rounds were fired at about the same velocity of the 7.92x57mm rounds !  They were very similar to the 50.cal's 

Combining round weight and velocity, the kinetic energy from both calibers were about the same ! 

Where were you let to believe they were 'weak'  

Are you sure your not mixing it up with the 20mm low velocity Mk108 cannon !  

You seem to be 'very' fond of U.S. planes and equipment !

And yes the Bf109 would defidently turn inside the P-47 at high speeds !

The P-47's only real advantage in maneuverability, was its roll rate !


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## Anonymous (Feb 25, 2005)

Soren said:


> RG_Lunatic said:
> 
> 
> > The MG131 13 mm rounds were so weak they'd have a hard time seriously hurting a P-47.
> ...



Soren - Lets look at the facts. Here are the figures for the .50 BMG, the MG131 13mm, MG151/20, and MK108:

```
Gun Specifications
Weapon     Nation  Cart (mm)  Ammo Type  Prj Wt.(g)  MV (m/s) (g/mm2)  Mz. Power  RoF         Gun Wt.
--------------------------------------------------------------------------------------------------
.50 M2 BMG  USA    12.7x99     AP/Ball      48.6      870      0.383      1.0    750-850       30 kg
MG131 13mm  Ger    13 x 64B    HET          34        750      0.256      0.5    840(sync)     17 kg
MG 151/20   Ger    20 x 82     Mine         92        785      0.292      1.5    740/500(sync) 42 kg
MK 108      Ger    30 x 90RB   Mine        312        505      0.441      2.2    600           60 kg
```



Soren said:


> Combining round weight and velocity, the kinetic energy from both calibers were about the same !
> 
> Where were you let to believe they were 'weak'



There's no "belief" involved, the math does not lie. The MG131 13 mm round has half the kinetic energy of the .50 BMG - do the math yourself if you need convincing. The muzzel power figures given above are calculated for the KE of the round and then divided by the KE of the .50 BMG, giving a 1.0 value for the BMG and a value relative to the BMG round for all others (it's easier to relate them this way). Furthermore, the BMG round's velocity is actually that measured at 78 feet, where the MG131 velocity is at the muzzel, so the BMG muzzel power is actually understated (at the muzzel it's about 890 m/s).

The MG131 13mm also has only 75% of the sectional density of the BMG round, and it has much poorer ballistic shape. At 200 meters the MG131 has lost 23% of its velocity, where the BMG has lost only 10%, so the MG131 looses more than twice as much velocity as the BMG with distance. And for reference the MG151/20 looses 26.5% of its velocity in the first 200 meters.

As you can see, combining the round weight and velocity the BMG is far superior to the MG131! The MG131 was a very weak "heavy" machine gun. - QED



Soren said:


> Are you sure your not mixing it up with the 20mm low velocity Mk108 cannon !



Not at all. The MG151/20 had poor range performance because of its poor sectional density, poor ballistic shape, and medocre muzzel velocity.



Soren said:


> You seem to be 'very' fond of U.S. planes and equipment !



Some. In general, US fighters were much better than people here give them credit for. People here want to assume they engaged in the kind of combat favorable to their opponents, but generally speaking US planes controlled that aspect of the engagement and were able to dictate the nature of combat, which was based upon maintaining high speeds.



Soren said:


> And yes the Bf109 would defidently turn inside the P-47 at high speeds !



And what do you base this assertion on? The 109 lost turn performance with increasing speed, the P-47 did not. Also, the P-47 could roll while pulling G's with almost no loss of roll rate, the 109 could not do this (neither could the Spitfire, P-51, F4U, F6F, etc...).



Soren said:


> The P-47's only real advantage in maneuverability, was its roll rate !



That's not true, but at speed the difference in roll rate alone is enough to nullify any turn rate advantage the 109 might have had (but it didn't).

=S=

Lunatic


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## Udet (Feb 25, 2005)

Guys, there is no doubt the P-47 is another one of the several great fighters of the war, but it was not perfect either.

Losses of P-47s in air combat with Bf109s and Fw190s were high RG.

USAAF veterans who naturally praise it like hell, have told me a dogfight with a Fw190 was an extremely close match, and the forecast on the outcome of the combat would rather be a withheld one. Some even used the word "fearsome" to describe the Butcher bird.

As to the Bf109 fighting the Thunderbolt, in some aspects the P-47 could surpass the 109 and viceversa. See the famous encounter of Gunther Rall who sent two P-47s down in quick succession flying his Bf109 just to get shot down himself after that, due to the overwhelming numbers of P-47s in the area.

Putting the level of pilot aside there (Gunther Rall) it is just one case that proves the P-47 and the Bf109 were both tough cookies.

RG, the allied historians have applied the term "outclassed" to describe the German planes indiscriminately totally losing the ground.


Now RG, let´s see this:

"In general, US fighters were much better than people here give them credit for."

Beg your pardon? It appears to me that statement applies not to the USA fighters but to the Germans!

As victors, naturally, they depict absolutely all allied fighters as superb flawless marvelous creations. On the other hand, the German fighters get little credit.

It has been the German fighters who have been defamed like hell by the bulk of the allied historians. 

RG, try to answer this:

Just like allied literature puts it, the Bf109 began losing manouverability after the G-6 version...blah, blah, blah..."the model was starting to show its age". Didn´t a similar thing happened in the case of the Spitfire?

Do you think the Spitfire evolved from the MkI to the MkXIV, ending with the Mk21 version without losing some its original features?

The fuselage got redesigned, heavier in general, more powerful (heavier) undercarriages were fitted. The chances of a Mk21 against any German opponent, 109 or 190 A and/or D or Ta152 were not too promising.

Being issued with more powerful engines and with sets of more powerful weapons of course affected its handling.

It did!! And no one ever mentions anything on that.


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## Soren (Feb 25, 2005)

First off all sorry i ment the MG-FFM not the Mk108.

Anyway Lunatic when comparing the KE of two rounds, then it is always a good idea to compare them with the same projectiles 

You can't compare AP projectiles energy with an HET's for christs sake  

The HET projectile is ment to blow an aircraft to pieces with Chemical Energy, while an AP round is ment to deliver High Kinetic Energy with a hardnened core inside, so it can penetrate the enemy Aircraft's armor by sheer KE !!

The 12.7mm 50.cal and the German 13mm round bear similar KE with AP projectiles. The 13mm AP projectile travels at over 800m/s while the less heavy 12.7mm round travels at 853m/s 

Also the fact that the MG131 had a rate of fire of around 900rpm, is advantage in its own right ! And its HET rounds will cause some nasty surface damage if it hits an enemy plane ! If you for example hit one of the wings with a 5-7 of these, the plane will be very unmaneuverable and hard to control !


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## CharlesBronson (Feb 25, 2005)

Sorry Soren, But actually it dont.

Here some ballistic tables. Velocity values for 13x64B API-T







Ballistic tables for HEI-T






The problem with this gun was the short cartrigde case.


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## Soren (Feb 25, 2005)

Wait a minute !

Sorry my fault, i have apparantly mixed it up with the MG151/20! 

I stand corrected.


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## Anonymous (Feb 25, 2005)

Soren said:


> Lunatic when comparing the KE of two rounds, then it is always a good idea to compare them with the same projectiles
> 
> You can't compare AP projectiles energy with an HET's for christs sake
> 
> ...



Your data is just flat wrong. See this post on this board for the BMG data. As you will see the velocity of the 48.5 gram AP or Ball rounds is 2810 fps = 857 mps measured 78 feet from the muzzle. At the muzzle, this comes out as about 870 mps. The M1 incendiary round velocity is 2950 fps = 900 mps at 78 feet from the muzzle, which measures about 915 mps at the muzzle. The M8 API round velocity was 2910 fps = 887 mps at 78 feet, or about 900 mps at the muzzle. The WWII M8 round weighed about 44.5 grams, the M1 incendiary about 42 grams.

Then there is the issue of the actual German AP/I round performance (pure AP was not used). From Rheinmetall-Borsig - Maschinengewehr Mg 131/13mm tests (1943/44):

13mm Panzergranat Patrone L'spur El. o. Zerl. (AP/I Round)
Geschossgewicht (Projectile weight) 38.5g
Mündungsenergie (Muzzle energy) 975 m/kg
Anfangsgeschwindigkeit (Initial speed) 710 m/sec
time-to-distance (m/secs): 100m/0.151, 200m/0.325, 300m/0.523, 400m/0.748, 500m/1.004, 600m/1.292, etc...

As you can see the round is NOT heavier than the BMG rounds! And the velocity of *710 m/s* is far less than the "over 800 m/sec" you quoted. If you do the math on it, I think you will find this round has very similer, but probalby lower muzzle energy than the HET round, since it is only 11% heavier, but is 8% slower, and velocity is squared in the KE calculation. However, it will hold it's velocity a little better because of its slightly better sectional density and tremendously better ballistic shape.

When I did my comparision tables (about 2+ years ago) I did not have data for the WWII M8 API round, so I had to use the AP/BALL round performance, but overall energy and performance will come out comprable to the AP/BALL rounds. The reason is simple - in the end the round must conform to the energy requirement of the gun. The projectile weight vs. the velocity must fit within fairly narrow parameters to operate the recoil or gas system.

So as you can see (I hope), the MG131/13mm was a very weak gun for its caliber. The reason is simple - it was an upgrade for 7.9 mm guns like the MG17 or MG81. It had to fit in the same space and mount on the same mounting points as those rifle caliber guns.

=S=

Lunatic


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## Soren (Feb 25, 2005)

Lunatic didnt you see my previus post ?  

I know i was wrong, i aparantly mixed up some data.

However the 50.cal had a normal velocity of 853m/s, and 890m/s for aircraft ammunition.

However i ca't see how you define the MG131 as weak !! It could easely rip holes in a P-47 and its 900rpm is also an advantage !


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## CharlesBronson (Feb 25, 2005)

Even it cannot compare with the .50 "Ma deuce" wasnt a bad weapon.

His strong point was high rate of fire, 900 rpm is defensive enplacements. It drop slightly thanks to a neat electric primer to 840 rpm in sincronizated fire like FW-190 an BF-109.






The source of relative low velocity is his case wich have the same length that a .30 US Garand round.






Anyway the rate of fire and low recoil give it a concentrated cone of fire that could devastated a single engine plane. For example Erich Hartmann was a real fanatic of this gun, many times when he encounter a formation of russian bomber with escort, he engaged the fighters using only this heavy machine gun saving the Mauser cannon for sturdiers twin engined-Pe-2 and DB-3. In other ocasion he blasted away 3 P-39 Airacobras in matter of minutes using only MG-131 due his cannon was jammed. 

A picture of the gun adapted for sincronized fire.


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## Soren (Feb 25, 2005)

Yes the rate of fire was defidently an advantage  And actually it was more like 930rpm !

Also the nose mounted low velocity 20mm MG-FFM could really do some serius surface damage !


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## Anonymous (Feb 26, 2005)

Soren said:


> Lunatic didnt you see my previus post ?



I was editing my post, with several delays for phone calls, when CB and you posted. It is hard to get tables to line up in this editor.



Soren said:


> I know i was wrong, i aparantly mixed up some data.



NP, we all make goofs sometimes.



Soren said:


> However the 50.cal had a normal velocity of 853m/s, and 890m/s for aircraft ammunition.



Jeeze, I've given you the data strait out of the manual. And the manual is edited to peacetime specs, in wartime ammo was loaded hotter. The velocity of the .50, it depends on the ammo. Check the link to the other thread I gave for velocity info, and then factor in that these figures are taken at 78 feet and must be adjusted up to get an actual muzzle velocity. Then factor in that WWII ammo was loaded hotter than peacetime ammo. Normal quoted WWII figures are 870 m/s for the .50 AP/Ball round at 78 feet, and 880 m/s for the Hispano 20mm at 90 feet (Actually the ANM2 version of the Hispano II).



Soren said:


> However i ca't see how you define the MG131 as weak !! It could easely rip holes in a P-47 and its 900rpm is also an advantage !



Hmmm.... .50's fired at 800-850 rpm stock, 950-1050 if the "nickle trick" was used (very common for the P-51B and inner pair of guns on the P-51D), but this was not generally done on the P-47D. The P-47N on the other hand (at least the late models) had the .50 M3, and fired at 1200 rpm. The MG131/13mm fired at a maximum syncronized speed of 840 rpm, but this also could be lower depending upon engine rpm. Overall, 800 rpms for both guns are reasonable estimates, which means the P-47 has 4 x the volume of fire as compared to the MG131's of the 109K. Alternatively if you want to use maximums, the max rate of fire of the standard BMG is 850 rpms.

Now lets consider the kinetic energy of the rounds. At the muzzle, using the figures for the MG131 API vs. the M2 AP round (I have not run the ballistics for the M8 API, its a very involved process), we get:

M2 AP at 0 meters = 48.6 x 867 x 867 = 36532085.4
MG131 API at 0 meters = 38.5 x 710 x 710 = 19407850

M2 AP at 100 meters = 48.6 x 822 x 822 = 32838242.4
MG131 API at 100 meters = 38.5 x 619 x 619 = 14751698.5

M2 AP at 200 meters = 48.6 x 778 x 778 = 29416802.4 
MG131 API at 200 meters = 38.5 x 539 x 539 = 11185058.5

M2 AP at 300 meters = 48.6 x 736 x 736 = 26326425.6
MG131 API at 300 meters = 38.5 x 472 x 472 = 8577184

So as you can see, at 0 meters the .50 AP has 88% more kinetic energy than the MG131 API. At 100 meters the advantage grows to 123%, at 200 meters to 163%, and at 300 meters it has grown to 207%. So in terms of kinetic energy, the .50 is more than double the power of the MG131 at 100 meters, and more than triple the power at 300 meters. And it just gets worse with increasing range.

The MG131/13 was a very weak HMG. It was about 2.5x more powerful than the 7.9mm guns it replaced, and had a little better ballistics too, but compared to other 12.7mm class HMG's it sucked! Why can't you accept this fact?

=S=

Lunatic


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## Anonymous (Feb 26, 2005)

Soren said:


> Yes the rate of fire was defidently an advantage  And actually it was more like 930rpm !
> 
> Also the nose mounted low velocity 20mm MG-FFM could really do some serius surface damage !



The MG-FF and MG-FFM were percussion primed and could not be synchronized, so they were never mounted in the nose. The MG151/20E was the syncronized 20mm gun. It fired at about 500 rpm when synchronized, about 750 rpm when free firing. The MG131/13 fired at 840 rpm maximuim when synchronized, but this was a maximum and depended on optimal and stable rpm, typical RoF was lower. Unsynchronized, I believe the MG131/13 could fire at something like 1050 rpm (relevant for bomber defensive gun installations)???

=S=

Lunatic


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## Soren (Feb 26, 2005)

Lunatic those calculations of KE you provided are WAY off !!

Here's the correct KE amount:

MG131 AP at 710m/s= 9703.925 J

M2 AP at 867m/s= 18266.0426 J

MG131 HET at 750m/s= 10828.125 J

Also all the info i got on the 50.cal gives it a velocity 853m/s for landbased weapons and 870m/s for aircraft, and it aint peacetime ammunition 

The Bf-109K-4 had the 20mm Mk108 in its nose (not the MG151/20), and its rounds were able to cause some serius surface damage if it hit an enemy plane !.


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## Anonymous (Feb 26, 2005)

Soren said:


> Lunatic those calculations of KE you provided are WAY off !!
> 
> Here's the correct KE amount:
> 
> ...



Jeeze - I was giving the logic for relative power. The equation for ke is:

_KE = 1/2 (mass x velocity squared)_

Because it's a relative figure, we don't need to worry about 1/2, since it ballances for both sides. I suppose I should have worked it out fully to avoid confusion.

1/2 x 36532085.4 = 18266042.7, which is in grams. 1/1000 x 18266042.7 = 18266.042 which is in joules (i.e. kilograms) - and what do you know it matches your figure almost exactly!

I didn't give an terms of measure for the figures. They're in half grams newtons - LOL! The point is it doesn't matter what the terms are for relative values.

Anway, the math and logic is correct, the relative ke figures which were the point of the whole thing are correct!



Soren said:


> Also all the info i got on the 50.cal gives it a velocity 853m/s for landbased weapons and 870m/s for aircraft, and it aint peacetime ammunition



I'm not disputing those figures. I used 867 m/s for the AP round.



Soren said:


> The Bf-109K-4 had the *20mm* Mk108 in its nose (not the MG151/20), and its rounds were able to cause some serius surface damage if it hit an enemy plane !.



I assume you meant to type 20mm. Yes I know this, but since that gun is virutally useless in a mutually aware dogfight what does it matter? "_If it hit an enemy plane_" is the operative phrase here. In a mutually aware high speed fight against a late model P-47 the chances of that are practically nil. The gun can't even be fired in a turn!

=S=

Lunatic


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## Chiron (Feb 26, 2005)

that movie was awesome!!!!!!!!!!!!


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## Soren (Feb 27, 2005)

> Because it's a relative figure, we don't need to worry about 1/2, since it ballances for both sides. I suppose I should have worked it out fully to avoid confusion.



Its allright !




> I assume you meant to type 20mm.



No i meant 30mm !   

Its alright as you said, anyone can goof up !


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## Anonymous (Feb 28, 2005)

Soren said:


> > Because it's a relative figure, we don't need to worry about 1/2, since it ballances for both sides. I suppose I should have worked it out fully to avoid confusion.
> 
> 
> 
> ...



Ahh but there was no "goof". I never gave terms of the KE measures. The point was to show the relative hitting power advantage of the .50 BMG over the MG131/13, which was done correctly. The BMG is more than twice as powerful at 100 meters, and more than three times as powerful at 300 meters. This is why I say the MG131 was a very weak HMG.

=S=

Lunatic


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## Soren (Feb 28, 2005)

That response was for you saying 20mm instead of 30mm  So there you did goof up !

Anyway the MG131 wasnt a weak gun, because then it wouldnt have replaced the 7.9mm guns.  

The 12.7x99mm 50.cal's were better yes, but in the end the size of the hole in the enemy aircraft would be 12.7mm with this round and 13mm with the other


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## mosquitoman (Feb 28, 2005)

a difference of 0.3mm wow what a difference


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## Anonymous (Feb 28, 2005)

Soren said:


> Anyway the MG131 wasnt a weak gun, because then it wouldnt have replaced the 7.9mm guns.



The 7.9 mm gun was a VERY weak gun! It has less than half the hitting power of the 13mm, and only about 1/5th the hitting power of the .50 BMG, and it looses energy even faster than the 13mm making it almost useless at 300m.



Soren said:


> The 12.7x99mm 50.cal's were better yes, but in the end the size of the hole in the enemy aircraft would be 12.7mm with this round and 13mm with the other



If it even penetrated, at any reasonable range (250m+) it was quite likely to just bounce off. After penetrating the skin of the target, it didn't have much energy left to do any real damage.

Was it better than the 7.9 mm? Most certainly. But it really fits better as a heavy LMG than to be classed with the true HMG's like the .50 BMG or Bresin UB 12.7mm.

=S=

Lunatic


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## Soren (Feb 28, 2005)

It can be classified as a weak HMG yes, but it wasnt weak ! It could easely penetrate the thin skin of an airplane and most of whatever behind it. The 7.92mm S.m.K.H. projectile could penetrate 20mm of 90 degree armor at 550m 

The Normal Vo for the 7.92mm machineguns were 890m/s.


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## Anonymous (Feb 28, 2005)

Soren said:


> It can be classified as a weak HMG yes, but it wasnt weak ! It could easely penetrate the thin skin of an airplane and most of whatever behind it. _The 7.92mm S.m.K.H. projectile could penetrate 20mm of 90 degree armor at 550m_
> 
> The Normal Vo for the 7.92mm machineguns were 890m/s.



The 7.92mm S.m.K.H. could penetrate 30 mm of homogenous plate at point-blank range at 90 degrees (perpendicular). At 100 meters it could penetrate 13mm, and at 500 meters it could penetrate 8 mm. This ammo made up only about 1-2% of 7.92 mm production in 1941 through March 1942, when production ceased. By Feb. 1943 all stocks had been depleted.

Besides, I don't believe this ammo was ever used for aircraft guns.

=S=

Lunatic


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## CharlesBronson (Feb 28, 2005)

The SmK(H), meaning *Spitzer mit Kern ( hart) = pointed with core (hard)* this was the best armor piercing version of the 7,9mm cartrigde. The projectile had a length of only 28.2mm, weighed 12.5 g and contained a tungsten core that was 22.5 mm long. The propellant gunpowder of the shell was increased to 3.6 g. 

Production of this ammunition type ceased in March 1942 because of an acute shortage of tungsten; still, SmK(H) cartridges continued to be issued to the troops and some to the Luftwaffe as late as February 1943. 
The initial speed was about 830 meter per second





[/b]


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## Anonymous (Mar 1, 2005)

My understanding from a brief research of this ammo is that it was for the MG34 only, and that it ruined out a barrel in something like 200 rounds, and that it was not used in the MG17.

=S=

Lunatic


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## Soren (Mar 1, 2005)

Lunatic the S.m.K.H. round penetrated 20mm of steel at exactly *550m* 

You want a reference with that one ?


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## Anonymous (Mar 1, 2005)

Soren said:


> Lunatic the S.m.K.H. round penetrated 20mm of steel at exactly *550m*
> 
> You want a reference with that one ?



Sure. But if you have one, it's wrong! The figure at 500 meters was 8mm penetration at 90 degrees.


Source: http://www.wwiivehicles.com/html/germany/guns.html

Panzer Truppen The Complete Guide to the Creation and Combat Employment of Germany's Tank Force 1933-1942, Thomas L. Jentz, 1996 

Panzer Truppen The Complete Guide to the Creation and Combat Employment of Germany's Tank Force 1943-1945, Thomas L. Jentz, 1996 

Even with an initial velocity of 890 m/s, the round has poor sectional density. Lets calculatate it. The round weighs ~12.5 grams and has a radius of ~4mm. Area of a circle = Pie * radius squared.

3.14 x 4 x 4 = 50.24 square mm.
12.5 grams / 50.24 square mm = ~0.25 g/mm squared.

Lets compare this 13mm API-T, which has similar ballistic shape. Weight is 38.5 grams and radius is 6.5 mm.

3.14 x 6.5 x 6.5 = 132.7 square mm.
38.5 grams / 132.7 square mm = ~0.29 g/mm squared

So as you can see, the sectional density of the 7.92 mm S.m.K.H. round is ~12% less than the 13 mm API round, which means it will have inferior ballistcs. It's also not a tracer round, meaning it will have even more inferior ballistics. It's also starting at 890 m/s which means it will slow dow faster at the beginning because of the higher mach speed.

By 500 meters the 13 mm API-T was down from an initial velocty of 710 m/s to 368 m/s, a loss of 48% of its initial velocity. It is clear the 7.92 mm S.m.K.H round would have at least 15% worse velocity retention.

There is no way that the 7.92 mm S.m.K.H could penetrate any 20mm of steel at 500 meters. Its velocity is down around 400 m/s at that range! And by 550 meters it's going sub-sonic!

=S=

Lunatic


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## Soren (Mar 1, 2005)

> Sure. But if you have one, it's wrong! The figure at 500 meters was 8mm penetration at 90 degrees.



No it isnt, yours is !  My primary reference is the book 'MG34-MG42 Universal machineguns' and varius other books about military surplus ammunition, plus experience in firing many of the rounds myself.

The *website* you quoted is notourisly inaccurate ! Just look at some of the other penetration stats !  





> So as you can see, the sectional density of the 7.92 mm S.m.K.H. round is ~12% less than the 13 mm API round, which means it will have inferior ballistcs. It's also not a tracer round, meaning it will have even more inferior ballistics. It's also starting at 890 m/s which means it will slow dow faster at the beginning because of the higher mach speed.



What ? A tracer-round isnt more accurate than a normal round  

The most accurate round you can get is a Boat-tail round, wich the Germans invented btw 

Also im not comparing the 7.92mm round with the 13x64Bmm round.



> By 500 meters the 13 mm API-T was down from an initial velocty of 710 m/s to 368 m/s, a loss of 48% of its initial velocity. It is clear the 7.92 mm S.m.K.H round would have at least 15% worse velocity retention.
> 
> There is no way that the 7.92 mm S.m.K.H could penetrate any 20mm of steel at 500 meters. Its velocity is down around 400 m/s at that range! And by 550 meters it's going sub-sonic!



Let me remind you that the 7.62x63mm 1950 AP round will penetrate 9mm of steel at 500m, and the 7.92x57mm S.m.K.H. round has been proven superior to the 30.06 AP round every time a test with the two were carried out. As a matter of fact i can testify to that, as i own alot of German WW2 surplus ammunition ! 

At our farm we had a 15mm thick metal plate hanging on a pole, and from about 400m away we would practice shoot after it. Whenever we used 1950's 7.62x63mm AP rounds, we found that they were unable to penetrate the plate, however our 7.92mm S.m.K.H. rounds penetrated every time, and they were 'clean' penetrations ! (I was impressed !)

Quote:

_Between 80 and 90 % of all 7,9mm ammunition produced was of the 7,9 sS (sS for schweres Spitzgeschoss = "heavy pointed bullet") type; the complete cartridge weighed 27g, it was 80.6 mm long and contained 2.7g of gunpowder; the projectile weighed 12.8 g and was 35mm long. When fired from a MG34 or MG42 (as well as from the other rifles using the cartridge) it had a typical V0 of 755 m/s. The regular sS projectile had the following penetration performance: 85cm of dry pine wood at 100m, 65cm at 400m, 45cm at 800m and 10cm at 1,800m; 10mm of iron at 300m, 7mm at 550m; 5mm of steel at 100m; 3mm at 600m.
The second most used type was the SmK (Spitzgeschoss mit Kern = "pointed bullet with core") bullet that measured 37.2mm, weighed 11.5 g and contained a hardened steel core (about 8% of all produced 7.9mm rounds). 
Another type was the SmK L'spur (L'spur = Leuchtspur = "bright trace" = "tracer") bullet that was the previous type combined with a tracer that burned for 800 to 900 m (a little less numerous than the SmK). In the picture at right a soldier is seen preparing a 7.92mm ammunition belt for a machine gun (presumably adding tracers at every seventh round).
The lS (leichtes Spitzgeschoss = "light pointed bullet") which had an aluminum core and therefore weighed only 5.5g which resulted in a higher speed of V0 = 925 m/s but of course also in a shortened total range (the bullet was used mainly in the air defense role; about 4-7% of the total production), the lS-L'Spur which with a length of 37.2mm and a weight of 6.1g was again the tracer version of the lS (less than 1% of total production). 
A version produced mainly for use with the MG 17 as aircraft armament was the so-called V-Patrone which had an increased powder charge that increased the V0 by 15%. This ammunition type was available with the PmK projectile ("Phosphor mit Stahlkern" = "phosphor with steel core") or with the B ("Beobachtung" = "Observation") projectile contained a little phosphor and exploded upon impact, the latter ammunition type was also known as the B-Patrone and was used as an incendiary round; both types are not counted in the 7,9mm production.

The final and most interesting bullet type was the SmK(H). The H stood for Hartkern (hardened core), this was the armor piercing version of the 7,9mm Infanteriepatrone. The projectile had a length of only 28.2mm, weighed 12.5 g and contained a tungsten core that was 22.5 mm long. The propellant gunpowder of the shell was increased to 3.6 g. The bullet had a penetration power of 20mm of plain steel at a range of 500m (90° impact angle). However, production of this ammunition type ceased in March 1942 because of an acute shortage of tungsten; still, SmK(H) cartridges continued to be issued to the troops as late as February 1943. while it was still inproduction, this ammo type accounted for 1 to 2 % of the production of 7,9mm Infanteriepatronen.

When the machine guns used the normal sS ammunition they achieved an armor penetration of up to 10mm and more at close ranges_


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## The Jug Rules! (Mar 1, 2005)

Soren said:


> The P-47's highest top speed was 433mph, the Bf109K-4 451mph
> 
> Also the P-47 would bleed energy much quicker  And the Bf109K-4 would turn inside a P-47 any day at any speed
> 
> I'd go for the Bf109K-4 !!



I thought the fastest speed for a Jug was 450mph.

The 109 has heavy controls at high speeds, so saying it can turn inside the Jug at any speed is a little bit too mutch...And if you are really in trouble, point the nose down and kiss that 109 goodbye!!!


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## Soren (Mar 1, 2005)

> I thought the fastest speed for a Jug was 450mph.



Not according to its specifications.



> The 109 has heavy controls at high speeds, so saying it can turn inside the Jug at any speed is a little bit too mutch...



First of all that was worse with early 109's such as the E series, K-4 less so. 



> And if you are really in trouble, point the nose down and kiss that 109 goodbye!!!



No arguement there  The P-47 was like stone when diving, and I've never heard that anything could follow it in a dive !


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## Anonymous (Mar 1, 2005)

Soren said:


> > Sure. But if you have one, it's wrong! The figure at 500 meters was 8mm penetration at 90 degrees.
> 
> 
> 
> No it isnt, yours is !  My primary reference is the book 'MG34-MG42 Universal machineguns' and varius other books about military surplus ammunition, plus experience in firing many of the rounds myself.



You have no experiance firing this round at 8/10th inch thick armor plates. If your reference book gives this figure, it is wrong. It is so far out of the bounds of reason it boarders on ridiculous.



Soren said:


> The *website* you quoted is notourisly inaccurate ! Just look at some of the other penetration stats !



Other sources give similar figures. I'll find some more for you if you like. Meantime, what page of your book is that figure quoted on? Can you scan or photo it and provide it?



Soren said:


> > So as you can see, the sectional density of the 7.92 mm S.m.K.H. round is ~12% less than the 13 mm API round, which means it will have inferior ballistcs. It's also not a tracer round, meaning it will have even more inferior ballistics. It's also starting at 890 m/s which means it will slow dow faster at the beginning because of the higher mach speed.
> 
> 
> 
> What ? A tracer-round isnt more accurate than a normal round



All other things being equal a tracer round looses velocity slower than a non-tracer round. The gas being emitted by the tracer hole at the rear of the round fills in some of the vacuum behind the round and reduces parasitic drag.



Soren said:


> The most accurate round you can get is a Boat-tail round, wich the Germans invented btw
> 
> Also im not comparing the 7.92mm round with the 13x64Bmm round.



I only compared these two rounds as an example because they have similar ballistic shape.



Soren said:


> > By 500 meters the 13 mm API-T was down from an initial velocty of 710 m/s to 368 m/s, a loss of 48% of its initial velocity. It is clear the 7.92 mm S.m.K.H round would have at least 15% worse velocity retention.
> >
> > There is no way that the 7.92 mm S.m.K.H could penetrate any 20mm of steel at 500 meters. Its velocity is down around 400 m/s at that range! And by 550 meters it's going sub-sonic!
> >
> ...



At our farm we had a 15mm thick metal plate hanging on a pole, and from about 400m away we would practice shoot after it. Whenever we used 1950's 7.62x63mm AP rounds, we found that they were unable to penetrate the plate, however our 7.92mm S.m.K.H. rounds penetrated every time, and they were 'clean' penetrations ! (I was impressed !)[/quote]

Practically no 7.92mm S.m.K.H rounds survived WWII, so how did some kids on a farm get hold of them to try them out? The few that exist are collectors items with collectors item price tags. And, what rifel would you have fired them from? They are known to ruin the barrel of a MG34 in just 200 rounds!

Besides, what does it matter. This ammo was never used on aircraft guns.

=S=

Lunatic


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## Soren (Mar 2, 2005)

> You have no experiance firing this round at 8/10th inch thick armor plates. If your reference book gives this figure, it is wrong. It is so far out of the bounds of reason it boarders on ridiculous.



As a matter of fact yes i have !  Although it wasnt armor plates, it was a metal plate !  (So the quality of the plate i ca't garantee !  




> Other sources give similar figures. I'll find some more for you if you like. Meantime, what page of your book is that figure quoted on? Can you scan or photo it and provide it?



Yes please provide ! And no i don't own a scanner.



> Practically no 7.92mm S.m.K.H rounds survived WWII, so how did some kids on a farm get hold of them to try them out?



Kids ??  And yes some did survive the war !  



> The few that exist are collectors items with collectors item price tags. And, what rifel would you have fired them from? They are known to ruin the barrel of a MG34 in just 200 rounds!



As a matter of fact it was done by accident with a K98k, and the bolt got stuck after the first round ! So we couldnt fire anymore than one round with that rifle. However even the normal S.m.K. round could penetrate the plate, at atleast 200m  



> Besides, what does it matter. This ammo was never used on aircraft guns.



The S.m.K. was ! And so was the V round !


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## Soren (Mar 2, 2005)

> It is so far out of the bounds of reason it boarders on ridiculous.



 No it damn well isnt !

Even the 'weak' 7.62 NATO AP round can take on a plate of much better quality !


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## Anonymous (Mar 2, 2005)

Soren,

Having done some further research on the issue, it appears the source doc you used is highly suspect. Probably a mistake in the translation.

Consider this. The Patrone 318 SmKH-Rs- L'spur 7.92 mm anti-tank round, fired from an anti-tank rifle, had an initial velocity of _over 1200 m/s_ and was able to penetrate 25 mm of mild steel at 300 meters at Zero degrees (i.e. perpendicular).

Other soruces state penetration of 13-14 mm @ 100 meters for the 7.92 mm SmKH round (fired at ~890 m/s).

If the 20mm @ 500 meter figure were correct it would mean that the Hispano 20mm AP and SAP rounds would have been able to easily defeat Panther armor, which we know was not true.

=S=

Lunatic


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## Anonymous (Mar 2, 2005)

Soren said:


> > It is so far out of the bounds of reason it boarders on ridiculous.
> 
> 
> 
> ...



Ummm.... that plate is of what quality? Besides, it's only about 10mm thick and we have no range figure for the hit.

=S=

Lunatic


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## Soren (Mar 2, 2005)

RG_Lunatic said:


> Ummm.... that plate is of what quality? Besides, it's only about 10mm thick and we have no range figure for the hit.
> 
> =S=
> 
> Lunatic



Its of alot better quality than the metal plate we practice shot against, thats for sure  And im sure the one on the picture is more like 15mm in thickness.

About the fault in translation, and the ability to penetrate I've done some research myself.

What i found was apparantly the German tested their AP round against different types of "Metal" plates, such as 'Steel' and just plain 'Iron' ! The results were very different from against 'Steel' to against 'Iron'.

_The regular sS projectile had the following penetration performance: 10mm of iron at 300m, 7mm at 550m; 5mm of steel at 100m; 3mm at 600m. _

For the normal Ss bullet: 10mm of 'Iron' at 300m, and 7mm at 550m. 5mm of steel at 100m and 3mm at 600m. A normal drop in penetration ability from 100-600m = 40%


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## Anonymous (Mar 2, 2005)

Soren said:


> RG_Lunatic said:
> 
> 
> > Ummm.... that plate is of what quality? Besides, it's only about 10mm thick and we have no range figure for the hit.
> ...



I think you are overestimating the thickness of the plate. Look at the round sitting right next to it lying on it's side. The base of the bullet (where it meets the casing) is 7.62mm. The plate is no where near twice that thickness!

I would suspect more drop in penetration between 100m and 600m. The round will slow down more than 40%, and penetration is based on something in between momentum and kinetic energy.

Anyway, I hope you see my point. If a 12.5 gram tungsten core AP round could have penetrated 20 mm of armor at 500 meters, a 130 gram AP round would have easily defeated any armor on the battlefield.

BTW, I have some experiance shooting 30-06 ammo at various things myself. When I was a kid we used to shoot up an old abandon dairy farm with a variety of guns, including M1's, Springfields, Enfields, and SKS's. We got a lot of ammo for free from one of the guys brothers who was a quartermaster at Camp Pendelton.

What I remember is that the 30-06 AP rounds would go all the way through an 8" railway tie. There was an old wrecked Chevy truck we shot up too. A 30-06 ball round would go through the hood, through the firewall, through the dashbord (metal), through the seat, through the back of the cab, through the front of the bed, and severely dent the far side of the bed. An AP round would continue out through the back of the bed.

The transmission was missing from the truck (I think someone had helped themselves to it) and the engine with no heads was laying on the ground near the truck. The 30-06 would also penetrate the engine block from some angles, the AP would pentrate the block and get into a cylinder. However, even the AP round only made a gouge in the flywheel, which is made of decent quality hard steel almost 3/4 of an inch thick.

We typically fired from ranges of about 80 meters (guestimate), using a convieniently placed concrete water feeder to sight from (and protect from possible ricochets).

=S=

Lunatic


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## Soren (Mar 2, 2005)

> I think you are overestimating the thickness of the plate. Look at the round sitting right next to it lying on it's side. The base of the bullet (where it meets the casing) is 7.62mm. The plate is no where near twice that thickness!



No it isnt twice the thickness of the7.62mm round (15.22mm), but its somewhere around 12-12.5mm I would guess.



> I would suspect more drop in penetration between 100m and 600m. The round will slow down more than 40%, and penetration is based on something in between momentum and kinetic energy.



Well thats actually a very normal drop, its about the same as with a 30.06 round.



> Anyway, I hope you see my point. If a 12.5 gram tungsten core AP round could have penetrated 20 mm of armor at 500 meters, a 130 gram AP round would have easily defeated any armor on the battlefield.



I see where your going, but you can't just increase the amount of weight and then figure it would penetrate alot more! Many things has to be taken into considderation, such as projectile shape, hardness, diameter etc etc...



> BTW, I have some experiance shooting 30-06 ammo at various things myself. When I was a kid we used to shoot up an old abandon dairy farm with a variety of guns, including M1's, Springfields, Enfields, and SKS's. We got a lot of ammo for free from one of the guys brothers who was a quartermaster at Camp Pendelton.



I used to shoot alot with my Mk4 Enfield, and it is in my experience the most accurate rifle from WW2, and it seems to get more accurate the longer the range believe it or not.  



> What I remember is that the 30-06 AP rounds would go all the way through an 8" railway tie. There was an old wrecked Chevy truck we shot up too. A 30-06 ball round would go through the hood, through the firewall, through the dashbord (metal), through the seat, through the back of the cab, through the front of the bed, and severely dent the far side of the bed. An AP round would continue out through the back of the bed.
> 
> The transmission was missing from the truck (I think someone had helped themselves to it) and the engine with no heads was laying on the ground near the truck. The 30-06 would also penetrate the engine block from some angles, the AP would pentrate the block and get into a cylinder. However, even the AP round only made a gouge in the flywheel, which is made of decent quality hard steel almost 3/4 of an inch thick.
> 
> We typically fired from ranges of about 80 meters (guestimate), using a convieniently placed concrete water feeder to sight from (and protect from possible ricochets).



Well sounds like you had alot fun ?  

My experience with the 7.92x57mm Mauser round and the 30.06 Springfield round are very similar. Whenever I shoot 7.92x57mm rounds, I only shoot German or Romanian surplus rounds, as i find the American made 8x57mm rounds to be grossly underpowerred  

Anyhow we used to shoot alot with the 7.92mm original Mauser rounds, and the 1950's 30.06 Springfield rounds, and found them to be pretty equal !

The normal 7.92mm Ss round will normally penetrate more than the normal 1950's 30.06 round (180gr), at all ranges, but they are both pretty equal actually. 

Like you, me and my pal actually once shot up an old Chevy's and Ford's motorblock, with a few German 7.92 S.m.K. rounds and also some Romanian 7.92x57mm surplus AP rounds ,at about 50m distance. The German round would go straight trough block every time, and leave a nice circular shaped intrance-hole, while the Romanian surplus would get stuck inside the motorblock, and leave a strange rectangular intrance hole. (The 30.06 behaved similar to the Romanian 7.92mm AP round if it hit very hard, thick and brittle metal)


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## Anonymous (Mar 2, 2005)

Soren said:


> > I think you are overestimating the thickness of the plate. Look at the round sitting right next to it lying on it's side. The base of the bullet (where it meets the casing) is 7.62mm. The plate is no where near twice that thickness!
> 
> 
> 
> No it isnt twice the thickness of the7.62mm round (15.22mm), but its somewhere around 12-12.5mm I would guess.



I really think it's a 10mm plate Soren.




Soren said:


> > I would suspect more drop in penetration between 100m and 600m. The round will slow down more than 40%, and penetration is based on something in between momentum and kinetic energy.
> 
> 
> 
> Well thats actually a very normal drop, its about the same as with a 30.06 round.



Sure, but like ALL 7.7 mm class ammo, the rate of velocity loss is quite high. Sectional density is the biggest factor in velocity retention, followed distantly by ballistic shape. Scale down a round to 1/2 size, and the sectional density drops in half, even if the ratio the projectile's cross-section to its length is unchanged.

Look at the sectional density of a cube (easy to visualize and calculate) - lets assume a cubic mm weights 0.1 grams for simplicity...

For a 4 mm cube: volume = 4 x 4 x 4 = 6.4 grams. Facing area = 4 x 4 = 16 mm. So the sectional density in grams/square mm = 6.4 grams / 16 mm = 0.4 grams/mm.

Now have the scale...

For a 2 mm cube: volume = 2 x 2 x 2 = 0.8 grams. Facing area = 2 x 2 = 4 mm. Sectional density = 0.8 grams / 4 mm = 0.2 grams/mm.

So the 7.9mm class ammo is going to loose velocity much faster than larger rounds. The only way around this fact is if the round in question is particularly long for its diameter, which is why the .50 BMG (and Brezin UB 12.7mm) do so well at maintaining velocity (combine with their very good ballistic shape).



Soren said:


> > Anyway, I hope you see my point. If a 12.5 gram tungsten core AP round could have penetrated 20 mm of armor at 500 meters, a 130 gram AP round would have easily defeated any armor on the battlefield.
> 
> 
> 
> I see where your going, but you can't just increase the amount of weight and then figure it would penetrate alot more! Many things has to be taken into considderation, such as projectile shape, hardness, diameter etc etc...



Sure, but the Hispano 20mm AP rounds were tested at muzzel velocities up to 920 m/s, and had 850 m/s velocity in production variants. The round shape is good for armor penetration. AP and SAP rounds used tungston-carbide penetrators, and solid tungsten shot was tested. So scaling up the side of the round would penetrate a lot more! There is every reason to believe that if a 7.92 mm S.a.M.K. round would penetrate 20mm of armor at 500 meteres, the Hispano 20mm fitted with a similarly proportioned tungston penetrator would penetrate at least 100 mm of armor at 800+ meters.



Soren said:


> > BTW, I have some experiance shooting 30-06 ammo at various things myself. When I was a kid we used to shoot up an old abandon dairy farm with a variety of guns, including M1's, Springfields, Enfields, and SKS's. We got a lot of ammo for free from one of the guys brothers who was a quartermaster at Camp Pendelton.
> 
> 
> 
> I used to shoot alot with my Mk4 Enfield, and it is in my experience the most accurate rifle from WW2, and it seems to get more accurate the longer the range believe it or not.



I like my Enfield too. I have an 1911 model that is in nearly perfect condtion. Next time I dig it out I'll post a photo.



Soren said:


> Well sounds like you had alot fun ?
> 
> My experience with the 7.92x57mm Mauser round and the 30.06 Springfield round are very similar. Whenever I shoot 7.92x57mm rounds, I only shoot German or Romanian surplus rounds, as i find the American made 8x57mm rounds to be grossly underpowerred
> 
> ...



Yes we had a lot of fun. Not much else to do out in the sticks but ride dirtbikes and shoot stuff up 

=S=

Lunatic


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## Soren (Mar 4, 2005)

> I really think it's a 10mm plate Soren.



Well I really think its a 12mm plate.(but it could be 10mm, i wouldnt know) 
Anyway it doesnt matter, I just know what my experience and books tell me about small arms and their penetrative ability. 




> I like my Enfield too. I have an 1911 model that is in nearly perfect condtion. Next time I dig it out I'll post a photo.



Looking forward to it !  You shoot with surplus ?



> Yes we had a lot of fun. Not much else to do out in the sticks but ride dirtbikes and shoot stuff up



The same here ! Except we didnt have dirtbikes, but ATV's


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## Anonymous (Mar 4, 2005)

Soren said:


> > I like my Enfield too. I have an 1911 model that is in nearly perfect condtion. Next time I dig it out I'll post a photo.
> 
> 
> 
> Looking forward to it !  You shoot with surplus ?



Never! I never shot the Enfield that much. I had access to lots of US surplus ammo for free, but not .303 surplus. When I did shoot the Enfield, it was always using brand new ammo. The last time I fired it I used PMC match ammo - about $15 per box of 20.

=S=

Lunatic


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## Soren (Mar 4, 2005)

RG_Lunatic said:


> Never! I never shot the Enfield that much. I had access to lots of US surplus ammo for free, but not .303 surplus. When I did shoot the Enfield, it was always using brand new ammo. The last time I fired it I used PMC match ammo - about $15 per box of 20.



I see, well i mostly shoot surplus, also for my Enfield. The worst thing about surplus ammunition is that its corrosive, so the barrell needs to be cleaned after firing.


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## Anonymous (Mar 4, 2005)

Soren said:


> RG_Lunatic said:
> 
> 
> > Never! I never shot the Enfield that much. I had access to lots of US surplus ammo for free, but not .303 surplus. When I did shoot the Enfield, it was always using brand new ammo. The last time I fired it I used PMC match ammo - about $15 per box of 20.
> ...



Which is why I don't use it for the Enfield 

I do shoot surplus and reloads from my M1's.

And I always clean the gun after shooting!

=S=

Lunatic


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## hellmaker (Mar 22, 2005)

Hey Lunatic... the movie's great... I fell in love with it...


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## DAVIDICUS (Mar 22, 2005)

I second that sentiment.


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## the lancaster kicks ass (Mar 22, 2005)

what forum was the thread with all the other videos in please??


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## cheddar cheese (Mar 22, 2005)

Probably the one with a title that implies video clips  Dont wait for someone to paste the link, find it yourself!


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## P51ace 16 (Mar 27, 2005)

so that is actual footage


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