Japanese Zero vs Spitfire vs FW 190

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

Night is different, arguably. But daytime bombers like the Baltimore were upgraded from .30 to .50 cal in the MTO.

So were dozens of bomber types all over the world, from Russia to Japan to the US
 
I think there is also a reason why the FAA acquired so many Martlets and Hellcats, and Corsairs, and for that matter Avengers. They were better suited to naval combat operations than what they had.

Do you think that being designed as Naval aircraft would have any bearing on them being adopted by the FAA to be used in the Navy?.
 
Night is different, arguably. But daytime bombers like the Baltimore were upgraded from .30 to .50 cal in the MTO.

So were dozens of bomber types all over the world, from Russia to Japan to the US

Your flogging a dead horse, bombers could not defend themselves regardless of what guns they had, they all needed escort fighters, including night time.
 
Lol tell that the B-29 pilots...

The point is that even with an escort, most bombers need as strong a defense as possible. When they put in a defensive gun in the Il2 - a 12.7mm UBT was the ultimate version - losses went down significantly with or without escorts.

The US medium and heavy bombers had multiple .50 cals for defense. Older types or those designed for European orders (like the Boston and the Baltimore) were upgraded to the heavier defensive guns (.50 cals) to extend their service life. They were still (usually) flown with escorts but the heavy defensive armament helped them stay alive. Older designs with lighter defensive guns like say the Wellington and the Blenheim were basically relegated to Coastal or night-time missions. Thousands of brave and highly trained aircrew lost their lives in Blenheims in the MTO as they couldn't survive missions with or without escorts. The only real exception being the Mosquito which had the superlative speed to enable evasion of fighters based on performance alone.

Nor were the Americans by any means unique in this. Most late model multi-engine bombers had heavy machine guns and / or cannon for defense:

Soviet Pe-2 was up-gunned to a 12.7mm defensive gun (which reduced the loss rate), as was the Il-4 (12.7mm UBT in the dorsal turret)
The successful though antiquated Italian SM.79 Torpedo bomber was given a 12.7mm defensive gun to survive encounters with Fulmars and Hurricanes in the Med
The G4M as I'd mentioned, had a 20mm tail gun. Later Japanese bombers like the Ki-67 had multiple (in that case x 5) 12.7mm defensive guns plus a 20mm.
The earlier German bombers with enough room (like the He 111 and Fw 200) were up-gunned with 13mm defensive guns, and later model German bombers had a mix of cannon and HMGs (Ju 188 had 20mm cannon and 3 x 13mm MG 131, the Do 217 had two 13mm guns, the ill-fated He 177 had no less than 2 x 20mm and 4 x 13mm guns)

So I would say it was a trend mate.
 
Hey guys,

A few bits of info concerning the continuing debate on fighter armament.

As I stated in my post#635 above: "The Air Ministry tests of .50 cal Browning vs .5" Vickers vs .303 cal MG (various makers) took place from 1932-1935." There was no available 20mm suitable for fighter use at the time. The result was the 8x .303 cal Browning armament specified for the Hurricane Mk I and Spitfire Mk I.

In late-1930s pre-war planning and wargame exercises, the Air Ministry considered the ratio of weapon effectiveness to be 1pt vs 2pts vs 4pts for the .303 cal vs .50 cal/.5" vs 20mm respectively.

In so far as none of the potential opponents at the time were fitted with armour or SSFT, the Air Ministry considered 8x .303 cal as the minimum acceptable, with the 20mm the clearly superior weapon (particularly vs bombers) but not yet available.

In 1935 the standard US fighter armament was 1x .50 cal and 1x or more .30 cal, depending on the service.

The US did not switch to 2x .50 cal plus ?x .30 cal, or 4x .50 cal (or more), until just before they entered the war - this change being largely brought about by what they learned from the early-war experience of the UK and France. Examples of this change in thinking (if needed) are the differences between the Buffalo/Wildcat/P-36/P-39/P-40/P-43 prototypes and/or early production variants, vs the first really combat ready models used by the US, such as the P-40D/E or F4F-3/-4.

I may be wrong but I do not recall any requests by the UK that the aircraft supplied by the US, after the US entered the war, have the .50 cal Brownings replaced with .30/.303 cal Brownings (which would have been quite feasible).

Based on the above I have to conclude that the US and UK both considered the war-time .50 cal clearly superior to the .30/.303 cal, at least once the opponents were carrying armour and SSFT.


During the war and post-war the UK switched to 20mm armament wherever possible, and post-war an all 20mm fit was adopted for all the new aircraft (I think, please correct me if I am wrong).

My understanding is that end-war/post-war the US considered the 20mm M3 to be worth 3x .50 cal M3. Although I have never seen a report that detailed the exact reasoning for this, I did run across a document that mentioned the effects of thicker skinning used on stressed skin surfaces and monocoque structures as used on the jets of the time (late-1940 to early-1950s). The document mentioned that the .50 cal had difficulty reliably penetrating the surfaces, particularly at higher obliquities (also mentioning the projectile tumbling problem) and still do adequate damage to internal components. Attempts to develop a ~.60 cal MG resulted in inadequate improvement in reliable penetration. Subsequently the 20mm was adopted, the reasoning being that a 20mm AP round would by its very nature be superior to a .50 cal AP round if that was what was needed, and that the destructive effects of the 20mm HE on skin and structure were so superior to the .50 cal that there was no comparing the two.

Based on the above I have to conclude that the US and UK both considered the 20mm clearly superior to the .50/.5" cal, at least as far effect on target is concerned. Maybe the 20mm could be considered overkill for fighter vs fighter combat in WWII, but I would think that the Air Ministry would have requested .50 cal/.5" be fitted instead of the 20mm (again, this would have been quite feasible) if there was any real doubt as to which was better?


(My apologies for not being able to post some original source documents for the above but my last computer crapped out ~2 weeks ago and I am still trying to recover the data.)
 
The US was never able to produce what they considered a reliable conventionally designed 20mm cannon, which is why the F-86 was still using .50 cals in the Korean War (and not doing very badly with them). They did finally get Hispano 404s into production (as the Colt Mk 12) but they felt it wasn't accurate enough and was prone to stoppages. It wasn't until the German type revolver cannons like the M39 (based on the Mauser 213) became available in the 50's that the US were confident enough in the 20mm to put them into wider use, though they still had problems with those guns wearing out the barrels. The M39s were replaced by the first multi-barrel (G.E. M-61) "gattling" types which arrived in the early 60's and are still in use today, which seem to be pretty effective.

As for the post above, again yes I agree round for round a 20mm is going to be better and more lethal than a 12.7mm round, but you do have to take into consideration ammunition capacity and reliability. The first generation 20mm cannon with their 60 round drum magazines were not necessarily the equivalent of two 12.7mm guns let alone three.

The 12.7mm had roughly equivalent effective range as the 20mm and if you had more of them with a lot more ammunition that did make a difference, especially for Carrier fighters.
 
Hey Schweik,

While I agree that the number of rounds available is important I do not know if it is important enough to change the question of balance (for lack of a better way to express it)? The Japanese could have installed Ho-103, an ~equivalent to the .50 cal Browning, with more ammo in place of the 20mm in the Zero if they had wanted to. Likewise, the Germans could have installed MG131 in place of the 20mm in the Me109 (including in the nose). But as far as I know they did not (at least not to any extent?).

I wonder how much the availability of gyro/lead-computing gunsights had to do with the switch to 20mm and smaller ammo loads post-war?
 
Last edited:
I think there is also a reason why the FAA acquired so many Martlets and Hellcats, and Corsairs, and for that matter Avengers. They were better suited to naval combat operations than what they had.
Concur. No hanks to the RAF. Beach aviators have no business messing with seagoing aviation. "Every two Fulmars/Fireflies/Baracudas means one less Lancaster."
Cheers,
Wes
 
Concur. No hanks to the RAF. Beach aviators have no business messing with seagoing aviation. "Every two Fulmars/Fireflies/Baracudas means one less Lancaster."
Cheers,
Wes
The Fulmar was our highest scoring FAA fighter, so I couldn't agree with you. The conversion kit Sea Hurricane the second highest scoring and the Seafire third with 99.
 
The US was never able to produce what they considered a reliable conventionally designed 20mm cannon, which is why the F-86 was still using .50 cals in the Korean War (and not doing very badly with them)

The US was still using the .50 in Korea because all the intended replacements had crapped out AND the guns used in Korea were the M3s (at least in the jets) and the ammo used in the Jets was the M23 incendiary round with much more incendiary material than the old M8 and since it was lighter, a much higher velocity which require less lead to get hits.
An F-86 in Korea was firing 120 rounds a second compared to the 80 rounds a second of an F5F, F4U, or P-51D. An F-86 carried 267 round per gun for a firing time of just under 14 seconds. If the US had used WW II M2 guns and WW II ammo things may not have gone so well.


The Japanese could have installed Ho-103, an ~equivalent to the .50 cal Browning, with more ammo in place of the 20mm in the Zero if they had wanted to. Likewise, the Germans could have installed MG131 in place of the 20mm in the Me109 (including in the nose). But as far as I know they did not (at least not to any extent?).
.

In theory the Japanese could have done that, at least later in the war, the Ho-103 not being in service until 1943 or so? (400 Ki-61s being fitted with imported German Mg-151 cannon). This assumes the Japanese Army and Navy actually co-operated :)

Sort of the same problem for the Germans. the MG-131 doesn't show up (at least in quantity) until 1941/42. It certainly is not a replacement for the MG/FF or MG/FFM 20 mm guns.
 
Lol tell that the B-29 pilots...

The point is that even with an escort, most bombers need as strong a defense as possible. When they put in a defensive gun in the Il2 - a 12.7mm UBT was the ultimate version - losses went down significantly with or without escorts.

The B-29 was pretty much in a class of it's own. One gunner could command several turrets/barbettes giving 4-60 guns aimed by one man at the same target. The sighting system was much more sophisticated than most other bombers used.

The IL-2 is an extreme case. No defensive armament to a very, very good 12.7mm gun (still manually aimed.




Soviet Pe-2 was up-gunned to a 12.7mm defensive gun (which reduced the loss rate), as was the Il-4 (12.7mm UBT in the dorsal turret)
The successful though antiquated Italian SM.79 Torpedo bomber was given a 12.7mm defensive gun to survive encounters with Fulmars and Hurricanes in the Med
The G4M as I'd mentioned, had a 20mm tail gun. Later Japanese bombers like the Ki-67 had multiple (in that case x 5) 12.7mm defensive guns plus a 20mm.
The earlier German bombers with enough room (like the He 111 and Fw 200) were up-gunned with 13mm defensive guns, and later model German bombers had a mix of cannon and HMGs (Ju 188 had 20mm cannon and 3 x 13mm MG 131, the Do 217 had two 13mm guns, the ill-fated He 177 had no less than 2 x 20mm and 4 x 13mm guns)

True on the PE-2 and IL-4 although both still suffered high losses,
the SM.79 was a bit different. the Italians hadn't actually standardized on the 12.7mm gun but they used a lot more of them than the 7.7mm guns. The SM.79 actually had three 12.7mm guns. one fixed out the front over the pilots windscreen (in the 'hump") one dorsal flexible mount out the back of the hump and one out the back of the ventral tub. One or two 7.7mm guns were mounted as waist guns. They did not change from 7.7mm guns in response to encounters with British fighters. The contemporary Fiat BR.20 bomber also used three 12.7mm machine guns.

The G4M used a 20mm gun and while effective if it hit it's chances of hitting were not good and it's overall performance as a defensive gun is questionable. However, as with so many other situations regarding aircraft armament one has to look at what the alternatives were. The other guns on the G4M were copies of the WW I Lewis gun (with or without licence) and a 7.7/.303 gun firing at around 600rpm with a 97 shot drum is hardly the last word in rifle caliber defensive armament, in 1940-42.

The German MG 131 was designed to fit into most spaces the MG 15/17 would, it was also, by a very narrow margin, the least powerful heavy machine gun cartridge. In part due to the requirement for a small, light gun. It was about 50% as powerful as the Russian 12.7mm UB ammunition as far as kinetic energy goes.
This also helps explain the Germans skipping over it to some extent and going for the 20mm cannon.

One 13mm MG 131 is hard pressed to equal a pair of rifle caliber Brownings for instance. 15 36 gram(average) projectiles a second vs 40 10 gram projectiles at about the same velocity (and the MG 131 bullets were not that streamlined). the Russian 12.7mm gun was firing 16-17 45-52 gram bullets per second at an extra 100meters per second. This made it a bit harder to control in a manual mount though.
61ddca93c535d06c4edcb9b4b5c0bd3cf89850d8_2_690x517.jpg

Round for the MG 131 on the left with the Russian 12.7mm ammo, everybody else's heavy machine gun ammo was in between.

During the war there was an awful lot of fitting what was available or likely to be available vs what was desired or planned for two to four years down the road.
The Germans made pretty much a hash of defensive armament for bombers. They had subscribed a bit too much to the fast bomber concept and then tried to leapfrog from manual aimed guns (fighting the slipstream) to remote aimed powered barbettes with the result that the few powered turrets/mounts they used weren't that good or were behind the curve when actually deployed.
image332.jpg

supposed to be a 13mm turret on a He 177.
One gun, and why does the the gun have a small amount amount of independent traverse to the turret itself?
 
Perhaps affinity for different caliber weapons also hinged on the quality of the versions they had available. Shell size not being the only criteria. MG 131 for example was a light weapon designed for use by aircraft (unlike the Browning M2) and had a pretty high rate of fire for an HMG, around 900 rpm. The Wiki notes specifically that it was considered a major improvement over the earlier 7.92mm LMGs especially as used by Bf 109 and Fw 190s. Not sure about reliability but German guns were usually pretty good.

The two biggest users of HMGs were arguably the US and the Soviets and they both had pretty good ones available. The British on the other hand had a love affair with the .303 round and had those nice Boulton - Paul powered turrets. Maybe hard to let that go. The Italians and Japanese also used HMGs a lot but I know the Italian Breda wasn't so great.

From my perspective as far as the American infatuation for the M2 .50 goes, it's from witnessing the effects of it on the range. It's a very impressive weapon. When I was in the army I spent a lot of time on the range because I liked to shoot and it was actually a way for me to basically have a day off. I never saw an Hispano 404 fired but aside from small arms I did see basically all the NATO weapons including the German, British, US, Italian and French LMGs, the M2, and some Warsaw Pact weapons like the PK and RPK. I also got to see some demonstrations of the M61 Vulcan which was extremely impressive but it used a vast amount of ammunition in a very short period of time. So your aim better be precise. Old hands from Vietnam told us that the VC used to just hide in the foxhole and wait for the buzzing sound to end. I also the saw the old Bofurs in use which to me seemed like a more useful weapon because it didn't blow the whole wad in ten seconds and had an impressive range.

The most impressive LMG in terms of accuracy and reliability from my (admittedly limited) perspective was the German MG-3. It had a high ROF and was very accurate especially on the tripod, and didn't seem to jam very often. The German soldiers were good at shooting short bursts from them, so good that with other LMGs they could shoot a single round at a time. Next was probably the FN MAG, which had a lower ROF but was also accurate and seemed reliable. The worst was the US M-60 which jammed a lot from what I saw and wasn't that accurate. Some of the ones we had were quite old and rattly, maybe Vietnam era (this was in the 80s). All of the LMGs tended to overheat quickly if you shot more than a couple of belts and required barrel changes.

To me, the "Ma Deuce" was just by far the scariest and most destructive thing on the range. We had a lot of old trucks and vehicles and other stuff on the range to shoot at - very far downrange. The M2 would consistently knock pieces off and it wasn't hard to hit targets very far away. The tracer rounds seem to float peacefully down toward the target and then just wreck it. The affinity for it by all branches of the US service personnel (and quite a few NATO troops) was not due to patriotism but due to seeing how effective it was. For example a lot of the same guys who loved the M2 despised the M-16 in those days and preferred the AK to it. (I gather the modern version of the M4 is better than the old M-16A1 and A2 that we had back then).
 
The British on the other hand had a love affair with the .303 round and had those nice Boulton - Paul powered turrets.
That "love affair" lasted exactly as long as the reliable belt fed 20mm was not available. Which came on-line about the same time as an acceptably reliable wing mounted M2 system. The soviets used 12.7mm guns in their aircraft, not because they preferred them, but because they couldn't loft more than ONE ShVAK 20mm at a time. Once they COULD, they standardized exclusively on 20mm and larger. In my opinion, for what its worth, the Yak-3P had maybe the best air-to-air armament of any fighter during the war, with its 3 B-20 cannons, all concentrated in the nose. Relatively light weight, fast firing, hard hitting
 
I wonder how many people here that argue for the 303 over the 50 BMG have ever actually held the rounds in their hand side by side? I understand the 20 mm was more destructive than a 50 per hit, but if you only have 2 20mm and either 60 or 120 rounds per gun vs even 4 50's with 450 rounds per gun then that is a big difference, especially when you spend most of your time missing the other plane. If I was in a P47 or a Corsair and could have 4 20mm with 250 rpg then that might make sense. But early in the war when your talking about Wildcats and P40's I think 4 50's was about optimum for what the allies were fighting, mostly single engine fighters and 2 engine bombers.

Let's not forget that Caldwell stated that they would have been better off at Darwin with 4 50's instead of the 4 303 and 2 20mm that they had
 
One of the FAA pilots I quoted upthread noted that (in his opinion) the Martlet had better armament than the Seafire he flew.
 
While combat warplanes can be pretty and flight performance numbers are interesting they really only exist to be flying weapon systems, it would be an interesting topic one day for aircraft that were made or failed due to their weapons.

Part of the success of the Fw190 probably had alot to do with the 4x20mm wing guns the early ones came with, a few random 20mm hits could still devastate or disable a fighter.
 
Especially in combination with their high combat speed, because it made the bounce so much easier. No idea there is an enemy plane around, and then you are hit with 30 or 40 x 20mm shells. Bye bye.
 
The early Fw190A-0's were armed with six 7.92mm MG 17's, followed by the A-1's, which replaced the outboard machine gun in each wing with a single MG FF 20mm

If only those crazy Germans had thought to put 50 cals on it instead, they could have won the war! :cool:





sorry
 

Users who are viewing this thread

Back