Putting a debate to rest: Shooting through the engine

There was a ton of drama and debate after we re-posted a discussion of the Fw 190 D-13’s armament arrangement from a Classic Under the Cowl. How could a bullet pass not only through the hub of the 190 but through the whole engine? And hey, wink, wink, if bullets pass through the engine, how do they not get all oily? I’ve trundled together three different drawings to give you guys a rough idea of what’s going on. All but the barrel of the cannon sits behind the engine, not totally inside of it. The barrel pokes into that hole you see in the engine case of the inverted V-12 (Jumo 213). The crank, over the top, is geared into the prop shaft via a big gear (with hole in the middle) in the nose case. The prop hub and spinner, too, have holes in the center to allow the bullets to pass through. It all looks roughly like this.