Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules
Regarding the WB 81 Z manual, there are 500 rds. per gun
did FW-190s use underwing cannons in the Jagdbomber role?
The WB 151 dual cannon pack was used operationaly by JG 11 (there is known FW 190 A5/U12 Wnr. 410266, flown by Leutnant Erich Hondt, 2./JG 11 in Husum Oktober 1943)
Weren't these cannon packs only used in the anti-bomber role ?
A couple of corrections:Mauser family Part 2, MG 151/20:
The cartridge overall length, the bolt stroke and the rate of fire (700-750 rpm) remained the same in the 15mm and 20mm versions. The reason that the cartridge case was shortened was that the 20mm projectiles were longer than the 15mm, so the case had to be shorter to keep the cartridges the same overall length. In the photo below (form the article on WW2 aircraft gun armament on my website) you can compare withe 15x96 of the MG 151 with the 20x82 of the MG 151/20.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 bolts travel was however good for the rate of fire , about 780-800 rpm. It can handle bullets between 92 and 120 grams.
Not so, as you can see the three gun barrels are the same (all are 7.92mm MG 17s). This pic is of any early model, before the 109E.Motorkanone MG 151/20 in B-109F.
The cartridge overall length, the bolt stroke and the rate of fire (700-750 rpm) remained the same in the 15mm and 20mm versions. The reason that the cartridge case was shortened was that the 20mm projectiles were longer than the 15mm, so the case had to be shorter to keep the cartridges the same overall length.
In the photo below (form the article on WW2 aircraft gun armament on my website) you can compare withe 15x96 of the MG 151 with the 20x82 of the MG 151/20.
CB: Schnaufer used the underbelly destroyer pod only briefly and his mounts had the standard upper 3cm weapons, in fact his last bird only had the upper 3cm fitted but had the FuG 218 Neptun installed when he went over to Stab NJG 4.
You also referred to "the shorter stroke in the bolt's travel" which would olnly be possible with a shorter cartridge: the bolt stroke length is directly linked to the overall cartridge length.Thanks for your corrections but note I wrote the cartridge case had to be reduced in length and not the cartrigde itself.
But others may not be...I am familiar with your website, there is no need to put a link to that in every post of yours.