The not the gun thats the problem, it's the radiator.
Use only the 7.62mm in a Bf109E and hit a radiator with some Yaks and Laggs or Mc. 202. There is no radiator damage. The to hit a radiator in a IL-2. The IL-2 radiator will damage with a thin smoke easily. So, IL-2 is a really wimp compared to Yaks or Laggs.
(sorry I can't write very well)