Luftwaffe Cannons and Machineguns topic.

[Tony Williams]

¿¿Huh...???? Tony are you sure about this ?, I saw several pics of german soldiers using former Luftwaffe MG 131s in the ground role, that is with a wooden or metal stock. If all the Mg 131 were electricallly primed as you said....how the gun was powered ?

That I don't know, but I'm certain that the Luftwaffe guns were electric primed: every source I know says so, and every cartridge I've ever seen is electric (the electric primer is easily recognisable because it has an insulating ring within it). There are a few of the experimental percussion ones in other collections, but they are very rare.

To convert an electric-pimed gun to percussion would not be a simple task, even if the ammo were available.

Tony Williams: Military gun and ammunition website and discussion forum

 

[CharlesBronson]

After looking for more info....you are correct.

The velocity marked here is wrong however.

But seems that also a percussion variant were used.


More images of this machinegun:

Do-217E turret:

Me-109K4 installation.

 

[CharlesBronson]

In the minute 3:10 of this video you can actually see a german tanker getting out of his vehicle with a MG 131 in hand.


View: https://www.youtube.com/watch?v=Hhd7PD8EGJg

 

[Tony Williams]

In the minute 3:10 of this video you can actually see a german tanker getting out of his vehicle with a MG 131 in hand.
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Are you certain that's an MG 131? At that distance, it's hard to be sure.

If so, the simplest solution would have been to fit a battery. In fact, if they wanted to make a proper job of it, they could have supplemented a rechargable battery with a generator coupled to the bolt movement, like these torches you can buy which you charge up just by shaking to and fro. However, I have never heard of such modifications to the MG 131, and Musgrave's 'German Machine Guns', which describes the various modifications to the gun in detail, states that all models were electrically-primed and makes no mention of ground use.

Tony Williams: Military gun and ammunition website and discussion forum

 

[CharlesBronson]

Are you certain that's an MG 131?

It is.

I saw also a pic of a MG 131 with the stock and no cables in a russian forum, let see if I can found it again. Aniway those were not the usual in Luftwaffe as you said.

In fact, if they wanted to make a proper job of it, they could have supplemented a rechargable battery with a generator coupled to the bolt movement, like these torches you can buy which you charge up just by shaking to and fro

It would more easy to get a spring loaded firing pin with percussion primers

 

[Tony Williams]

According to Musgrave, a decision was taken to make all MG 131s electric primed, even though it was less convenient for those in flexible mountings, because that simplified gun and ammunition procurement and made certain that no gun could accidentally be supplied with the wrong type of ammunition. That is consistent with the fact that the only - and very rare - percussion-primed rounds known come from the development process for the gun, before it was adopted.

Tony Williams: Military gun and ammunition website and discussion forum

 

[CharlesBronson]

According to Musgrave, a decision was taken to make all MG 131s electric primed, even though it was less convenient for those in flexible mountings, because that simplified gun and ammunition procurement and made certain that no gun could accidentally be supplied with the wrong type of ammunition.

Yeap, Now I am convinced, every source seems to agree on that. We could say that every airborne gun was electrically ignited.

There was however some rare examples of percussion operated ground combat guns like this:

 

[Tony Williams]

Well, that's certainly an MG 131. But considering that those guns would AFAIK only be pressed into service as a makeshift expedient - I have never heard that the MG 131 was ever adopted by the army - I find it hard to believe that anyone would go to the trouble of converting them to percussion firing and setting up a production line for percussion ammunition and setting up the supply chain necessary to get such ammo to the guns which needed it. It makes no sense. I will make further enquiries....

Tony Williams: Military gun and ammunition website and discussion forum

 

[CharlesBronson]

Lets talk a little about the ammo.

Munition of 13x64B for MG 131.

As I said before this was a reduced capacity case in comparative with other similar weapons.Very reliable however. It can manage bullets weight between 33 and 38 grams and shoot them at more than 700 m/s. All the bullets use a metal driving band weich is unusual in this relatively small calibre, the "B" in the designation indicates a Belt to adjust chamber headspace.

13 mm Panzergranatpatrone L'Spur

Solid steel armor piercing shot, with day tracer. Muzzle speed 710 m/s. Bullet weight 38,1 grams. The tracer endures about 1,5 secs enough for 700 meters flight. There was also a Phosphor filled variant wich improve the incendiary effect.

Armor penetration table for the 13 mm Panzergranate, the vertical columns indicates the plate thickness and the horizontal the angle (90 º being vertical ) The discontinued lines indicate the penetration with a 3 mm duraluminium plate at 20º on front, simulating an aircraft body.

Sprenggranate L'Spur

Explosive, tracer with head impact fuse. Even is dubious the real affectiveness of a HE bullet in this caliber it was widely used. Some variant even had a self destruction element despite it complicated fabrication. Bullet weight 34 grams, muzzle speed 750 m/s.


Brandgranatpatrone L'spur

Incendiary with tracer. Weight 33,5 grams, muzzle speed 755 meters per second. The filling is a mix of barium nitrate and magnesium.

 

[CharlesBronson]

Ikaria MG FF 20 mm

The first cannon in use with the newly created Luftwaffe. This design derivated from the WW1 Becker gun, this was copied and manufactures for the swiss SEMAG (Oerlikon) factory in the interwar years as the FF-F ( FF means flugel felst = wing mounting) .

The Berlin based firm Ikaria adquire the license for his manufacturing in ealy 1930s. Not very satisfied with the performance of the swiss gun some modifications were introduced to increase the muzzle velocity and the rate of fire.

The gun mechanism was very simple, a cylindrical spring move the bolt forward feed the round and having a fixed firing pin it shoots the cartridge just being rammed in the chamber. The only opposed force to the powder blast is only the mass inertia of the moving parts until the recoil forces overcome it and the extraction began. This is know as blow-back operation system or (more technically) "advanced primer ignition".


The simple blow-back mechanism in MG-FF.

The gun saw service experimentally in the Bf-109C and D, but only was broadly introduced in the BF-109E-3, also was part of the weaponry in the FW-190 (outer wings) until replaced with the more modern MG-151.

The ME-110 fighter carry 2 of these below the nose and some variants also had two in the rear cockpit as "Schrage musik" anti bomber guns.
Also was used in several bombers as an defensive armament.

Fixed MG FF in Ju-88A-14.

The MG FF weights 27 kg, had a rate of fire of 520 rpm, an overall length of 1260 mm and was feed by a 60 rounds drum magazine.

 

[Denniss]

It looks like the MG FF/M is missing, that's the MG FF modified to fire the Minengeschoss (Mine-shell). These mine-shells were thin-walled high explosive shells containing four times the amount of explosives than the earlier MG FF HE rounds. Due to changes to the recoil mechanism the FF/M was not able to fire the heavier FF rounds and vice versa.
The FF/M was introduced with the Bf 109 E-4 and the Bf 110 C-4 just prior to Battle of Britain.

There was also a 90-round drum available but I'm not sure about introduction dates.

 

[Tony Williams]

Due to changes to the recoil mechanism the FF/M was not able to fire the heavier FF rounds and vice versa.

This is correct but it might be worth adding some more information.

The MG-FF fired 134g projectiles at 600 m/s. The M-Geschoss weighed only 92g and although the muzzle velocity was increased to around 700 m/s this did not generate enough recoil to operate the MG-FF's mechanism, so it was modified to work with the lower recoil (thereby creating the MG-FFM, or MG-FF(M), or MG-FF"M" - various designations were used).

However, the Luftwaffe still wanted to use conventional HE-T projectiles because the original M-Geschoss design precluded the fitting of a tracer. So they lightened the HE-T shell by fitting a aluminium instead of brass fuze (117g total) and loaded it down to 585 m/s so it would match the recoil of the M-Gescoss. Later on, they introduced various types of pointed AP shell, also weighing around 117g.

There was also a 90-round drum available but I'm not sure about introduction dates.

Mid-war, I think - the drum was physically the same size as the 60-rounder, but packed more tightly. They also introduced a small 30-round drum for use in flexibly-mounted guns. And there was an electrically-powered belt feed for night fighters.

Incidentally, I believe that the 60-round drum was normally only loaded with 55 rounds as it was more reliable that way.

 

[CharlesBronson]

He, thanks for the input lads.

It looks like the MG FF/M is missing

Actually it hasnt, I just simply had no time to log in earlier:

Let see:


MG-FF/M variant:

The MG-FF/M was the gun prepared to shoot the special Minengesschos , this was a very thin walled explosive round wich higher capacity of explosive filling than the older models. However this 92 grams bullet had not enough recoil to feed the gun properly so a lighter cylindrical spring was needed. In order to armonisate all this the FF/M was introduced in 1940 with the Bf-109E-4 togheter with a new family of ammunition, wich ( to the headache of the ground crews) was not interchangeable with the FF ammo. The gun had a slightly improved rate of fire, about 540 rpm.

Gun armonization in Bf-109E-7 in the desert (a couple of FF/M cannons)

In outer wing Fw-190A-3.

There was also a 90-round drum available but I'm not sure about introduction dates.

I saw that in the JU-88A-14 nose. The drum was cilindrical and not conical like the 60 rounds one.

And be patient, I will put the ammo for this later.

 

[CharlesBronson]

Fw-200 using his belly mounted MG-FF for ship strafing, note that is loaded with 20 round magazines and not drums.

Minute 2:50


View: https://www.youtube.com/watch?v=kqly1pHyZ5E

 

[comiso90]

Thanks much Charles...
Fascinating...
6000 rpm! Wow..
How many rounds were typically carried?
Were German gunners able to change barrels in flight?
Did the rear firing Mg-17 record many kills? It looks like a folly to me.

 

[CharlesBronson]

6000 rpm! Wow..

What weapon are you refering with that ?

How many rounds were typically carried?

In wich one ? If you are talking about the MG-FF in Fw-200 there was 15x20 rounds magazines= 300 rounds.

Were German gunners able to change barrels in flight?

No, generally the barrels of this guns were changed by the groundcrew.

Did the rear firing Mg-17 record many kills? It looks like a folly to me.

It did not.

 

[comiso90]

What weapon are you refering with that ?

In wich one ? If you are talking about the MG-FF in Fw-200 there was 15x20 rounds magazines= 300 rounds.
.

>>The Ju-87D and the attack variants of the FW-190 could mount a WB-81Z below the wing to engage enemy infantry , this contain 3 MG-81z tilted down 32 degrees so the aircraft shoot downwards even in level flight, this layout unleash a rate of more than 6000 rpm... ¡¡¡ quite a Minigun.

 

[CharlesBronson]

You are correct, in this case the rate excedeed that figure, because 6 x1500 = 9000 rpm...nasty.

The MG 81s were feed by 150 round per gun in that emplacement.

 

[genkideskan]

Regarding the WB 81 Z manual, there are 500 rds. per gun.

 

[genkideskan]

Here are some closer looks.