Reply With QuoteA Quick change barrel means nothing since it isnt changed inflight by the Gunner. the Blackies get it done on the ground.
The teory behind was the 4 men inside the Ju-88 will fight togheter "improving the moral" of the crew, I wont be sure about it.
MG 131 part 2, bomber powered turrets:
Remote controled twin turret in He-177.
FDL-131
Barbettes Messerschmitt Me-210
Single barrel mounting. All The MG131s variant had the benefit of quick change barrel.
Electric powered turret EDL 131 in FW-200. Note the armor piercing (black) and HE ( yellow) rounds in belt.
Some sources used so far
"The machine gun Vol I, II & III James M. Chinn"
www.luftarchiv.de.
www.lexikon-derwhermacht.de
http://www.elgrancapitan.org/foro/index.php
www.tecnicamilitar-fateback.com
www.aeronautics.ru
Bf-109 in action part II- Squadron signal.
FW-189 in action- Squadron signal
Ju-88 in action part I and II- Squadron signal.
this will continue...
A Quick change barrel means nothing since it isnt changed inflight by the Gunner. the Blackies get it done on the ground.
well it didnt need high velocity and cyclic rate to punch through armor like a rifle caliber with AP Steel/Tungten core, since it used HE against thin armor plate and duraluminum and Plexiglass.Originally Posted by Panzerknacker
When the shooter and the target are already moving very fast having a fast muzzle velocity makes gunnery easier by reducing the need to lead.
I find MK108 fascinating. I have always wondered how much it influenced the development of the AGS-17. I believe I read from somewhere that there was a connection between the two, can't remember what it was though.
Pk:
Thanks! I am really enjoying this thread.
I am glad you re enjoying it.
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. It also was modified with the addtion of a quick change barrel.
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 MG-FF 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 like He-11, Ju-88, FW-200 as an flexible ofensive armament, mostly for ship strafing.
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. Caliber was 20x80mm with rebated rim.
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.
Not to derail a fascinating threa or anything but anyone want to bet thats Simba, Franz Von Werra's pet lion? Who else has a Bf109 and a lion cub?I
Interesting pics of the triple mounting of MG151 /15 in nose of He-280.
Between 1944 and 1945 a lot of surplus MG-151/15 were used as a drilling (triple) in the Sd.Kfz 251 half-track.
Awesome thread Panzer!
Ok...
Bullet weight in grams and velocity in meters per second is worthless to us Americans. Please use grains or ounces to refer to projectile weight from now on, and feet per second for velocity.
Thanks.
The germans dont use those measures and this all is from german sources but :Ok...
Bullet weight in grams and velocity in meters per second is worthless to us Americans. Please use grains or ounces to refer to projectile weight from now on, and feet per second for velocity.
Thanks.
a feet = .0.3048 meters.
a grain = 0.0648 grams, now use a calculator.
Tante grazie.Awesome thread Panzer!
Last edited by Panzerknacker; 12-07-2011 at 08:33 PM.
I re-post this info related withe the MG-151 because the earlier was deleted for hotlinking issues.
The Mauser MG-151 family Part 1:
As early as 1934 the Mauser technicians began the development of a new airborne weapon to replace and/or complemente the Oerlikons guns.
The MG 151 was designed in two different calibres at the same time, the heavy 15mm MG-151/15 and the MG-151/20 20 mm cannon. Interchangeability between both design was also provided.
The 15 mm heavy machinegun (incorrectly named cannon in some sources) was the first of the family to be introduced in service with the Me-109F2 in march 1941. The MG was operated by a short stroke recoil mechanism, both barrel and lock recoiled togheter and the the bolt is disingaged using a rotating bolts head.
MG 151/15 used a large capacity bottlenecked case with gave a high velocity to the proyectiles around 850-960 m/s. That provided a straigth flying path to target and improve the chances of hit. Due the generous muzzle speed the Ap bullet could defeat any aeronautical armor in that time, including the mitic "ironclad" ilyushin Il-2 Sturmovik. Its overall lenght of the gun was 1917 mm, width 190mm, weight 42,5 kg and it shoot at some 700 rpm.
-Profile of MG-151/15
-Inner squematic.
-Loading a 125 rounds belt in a Hs-129B-1.
-In Fw-200
Ammunition for 13mm MG 131:
Munition of 13mmx64B 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 aand 38 grams and shoot them at more than 700 m/s. All the bullets use a metal driving band, 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 endurance was circa 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, 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 m/s. The filling is a mix of barium nitrate and magnesium.
And the ammunition for the Mauser 15mm heavy Machinegun:
15x96mm Ammunition for the MG-151/15.
Panzergranatpatrone, L-spur.
Armor piercing steel shot, with tracer, projectile weight 72 grams initial speed 850 m/s. The tracer elemente endure at list 1100 meters.
Penetration table for Pzg.Ptr. L-spur. 25 mm at 100 meters and 13 mm at 600 meters, both in vertical (90º) plate and direct mode..
Brandsprenggranatpatrone
Incendiary-explosive. 57,5 grams bullet, muzzle velocity 960 m/s, pretty fast one.
Brandsprenggranate L-spur Mit Zerl.
Same as above but with an tracer and self destruction element in the bullet base. Green band.
and also....
Hartkern-Panzergranate ohne-zerl.
This is a pretty unusual variant. It consist in a miniaturized hard core Panzergranate 40 as used in the Panzers. Bullet weight 53,5 grams, it had an 9,5mm diameter tugsten-carbide core with a aluminium-magnesium envelope. It was propelled by 24,5 grams of gunpodwer an it can reach 1000 m/s. Due his cost a relative rarity it was to combat tanks only, no for air-to-air use. Probably it went to the Hs-129B-1 attack craft, and for some experimental 15 mm antitank rifles.
Penetration table of the Hartkern 15 mm bullet, 48mmm at 100 meters in a 160 kg/square mm steel ( wich is equivalent to a SAE 4340 alloy), excellent figure...
The penetration tables are extracted from : "Handbuch der Flugzegbau Bordwaffenmunition" 1977, Hans Riehl.
Mauser family Part 3, MG 151/20:
Despite the good characteristics in the 15 mm MG the german Air Force promptly favored the 20 mm gun. The air-to-air doctrine was turn to believe that is more likely to destroy an aircraft with high explosive shells and not just putting holes on it with AP ammunition.
An 20 mm bullet diameter was always considerer as the minimum practical explosive shell. The MG-151 was designed to accept all the family of the FF, including the high capacity Minen bullet.
There was some limitations to employ the same receiver and bolt of the 15 mm variant , the cartridge case had to be reduced in length, that and the heavier projectile gave as result a 100 m/s reduction in muzzle velocity compared with the 151/15. A shorter stroke in the bolt travel was however good for the rate of fire , about 780-800 rpm. It could handle bullets between 92 and 120 grams.
Mauser began the high scale production in 1941 and it was adopted first by the Bf-109F-4 in mid-1941. The MG-151 quickly replaced (or at list it was intended so) the older MG-FF in several types of aircraft. There was a pneumatically triggered variant for fixed mounting and other manually charged for flexible defensive laffettes. As usual the cannon was feed by a disintegrable metallic belt and air cooled. The cannon weights 41 kg, and it had a overall length of 1620 mm.It will be superfluous to describe all the aircraft wich employs this gun, some like the Me-109, Fw-190, Me-110G, Ju-88C, Ju-88G, Ju-87D, Me-210/ Me-410, He-177, FW-200, etc. It enough to say the it became the most used cannon trough the war
Gun layout in a Me-210.
Compared with the allied guns like the Hispano Mk-II the Mauser 20 mm was little less powerful, it had in his favor a much superior reliability and rate of fire. In the MG-151 the german pilot could be sure that in the 99,99% times he pulls the trigger the Mauser went off…thing that cannot be reproduced in the French-British cannon.
Cleaning the bore in MG-151/20, North Afrika:
Mauser MG 151/20 Electric
The differences with the normal MG-151/20 was purely internal. The spring loaded firing pin was replaced with a fixed needle wich was energizated by the 24v aicraft electric circuit. The sincronization device consisten in a electromechanical gear, the use of electricar primer wich was detonated by a spark, mean that a more instantaneous ignition was provided. That allowed the MG 151/20E to shoot through a high rpm 3 thick blade propellers like the BMW 801 engine and still had a rate over the 600 rpm. Production of the MG 151/20E were delivered almost entirely to the Fw-190 and the Ta-152H variants, some other aircraft in use were the Do-335 (2 above the engine), Me-209 stüfe II (wingroots) and the Me-309 (wingroots and above engine)
The 4 guns in a FW-190A-6.
Experimentally the fitting of an MG 151 pod under the fuselage to fire through the prop was tested. This apparently worked very well, providing a valuable improvement in firepower without the performance and handling penalties of the underwing pods. However, the belly gun had to be synchronised, which meant it had to use the electric-primed gun, whereas the engine gun used percussion priming. The risk of mixing up the ammo was considered too great, so the idea was dropped
MG 151/20E below Bf-109G-4.
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