Hi again,
Here's some more information on MG151/20 ammunition (quoted via the "Waffen-Revue").
Regards,
Henning (HoHun)
(The ammunition used in air combat was equipped with primers
that blew up the charge after some time to avoid collateral
damage on the ground. I don't know how this is called in
english (in german it's "Selbstzerlegung", literally
"automatic disassembling" :-) I called it "destruction" in
the list.)
The ammunition described was used in the german MG151/20
cannon.
Incendiary explosive tracer round:
total mass 205g
projectile 115g
warhead 2.3g Nitropenta + 2.1g electron-thermite
tracer 3.3s = 1300m
destruction a) none / b) at 1200m
propellant 14.8g Nz. R. P.
v0 705m/s
usage a) only against ground targets / b) in air combat
effect fragmentation, additional blast and incendiary
effect
penetration none
There were two variations of this round (additional to the
self-destruction primer), one bright tracer and one dim
tracer round. The dim tracers were used by night fighters to
avoid blinding of the pilot.
Explosive round:
total mass 183g
projectile 92g
warhead a) + b) 18.6g Nitropenta c) HA41
tracer none
destruction a) none / b) at 900 to 1200m / c) at 1400m
propellant 19.5g Nz. R. P.
v0 785m/s
usage a) only against ground targets / b) + c) in air combat
effect blast effect
penetration none
There were two variations of this round (additional to the
self-destruction primer), the conventional Nitropenta round
and a round with a 40% more powerful explosive that was only
used in air combat.
a) Armour piercing round / b) Armour piercing explosive round:
total mass 205g
projectile 115g
warhead a) none / b) 4g Nitropenta
tracer none
destruction none
propellant 18.5g Nz. R. P.
v0 705m/s
usage a) against ground and air targets
b) mostly against armoured ground targets
effect a) armour penetration
b) after penetrating at least 5mm armour: blast and fragmentation
penetration a) at 100m, 60degs impact angle 13mm armour of 120kg/mm**2
b) at 100m, 60degs impact angle 13mm armour of 150kg/mm**2
Armour piercing incendiary round
total mass 207g
projectile 117g
warhead 6.2g incendiary in metal capsule
tracer none
destruction none
propellant 19.8g Nz. R. P.
v0 695m/s
usage against merchant ships and light warships
effect after penetrating at least 4mm steel and traveling ca. 1m:
incendiary effect by burning capsule
penetration at 100m, 75 degs 15mm steel
Note that penetration is given against steel as used with
ship's hulls, not against armour steel.
Armour piercing incendiary round
total mass 202g
projectile 115g
warhead 3.2g incendiary (phosphor) in aluminium capsule
tracer none
destruction none
propellant 18.5g Nz. R. P.
v0 705m/s
usage against heavily armoured air targets and lightly armoured ground
targets, automobiles, trains, etc.
effect after penetrating at least 4.5mm steel at 60 degrees and
traveling 20 to 120cm: incendiary effect
penetration at 100m, 60degs impact angle 13mm armour of 150kg/mm**2
I've found an incendiary round mentioned that could eject
incendiary on 5 to 7 impacts and was much more effective
than the previously used rounds. I suppose that it refers to
this round.
While the MG151/20 ammo usually had a projectile mass/total
cartridge mass of 115g/205g, the older MG/FF's masses were
134g/202g. However, the MG151/20 had a higher muzzle
velocity. MG/FF ammo exisited in similar variety as the
MG151/20 ammo. The 30mm MK108 cannon's ammo was much
heavier: Its values were 330g/470g. Finally the 13mm MG131:
34g/85g (weight of ammo belt included)
The ammo belts were loaded with a pattern of different
rounds. One example of what a Bf 109F-4 used in 1941 against
bombers: MG151 2 incendiary explosive tracer, 2 explosive;
MG17 4 armour piercing, 1 full metal jacket, 1 full metal
jacket with tracer.
The MK108 was slightly unreliable and sometimes jammed.
There is a case in which a Me 109 suffered a stoppage after
firing the first round, but the single projectile fired
succeeded in blowing up a four-engined bomber anyhow.