[Broncazonk]

The MK 103 was introduced into service in 1943, well before the Do 335 or Ta 152.

The wing mounted MK 103 cannon was quite heavy, slow, and extremely inaccurate. And the recoil forces were enormous (2,000 kg per round with a muzzle brake {wing mounted} and 3,000 kg without {motor mounted}) which put significant stress (and movement) on the wings and mounts.

The motor mounted MK 103 cannon was just as heavy, just as slow (65-rounds/minute) and inherently inaccurate. (The motor mount didn't help the accuracy one bit.) "With a firing probability of 95%, it was calculated that 76 rounds would have to be fired from a range of 500 meters to achieve three hits on target. This figure rose to 203 rounds from 1,000 meters and 650 rounds from 1,500 meters." Dornier Do 335 by Karl-Heinz Regnat (Schiffer 2003)

A minimum of 76 rounds to get 3 rounds on target at 500 meters (95% of the time) is absolutely appalling inaccuracy. A fighter carrying the Mk 103 literally couldn't carry enough 30mm ammunition to get the job done.

Bronc