You saw 200 hit sprites? I'm thinking not.
With his 3.77% average in gunnery, to see "200" hit sprites he would have fired around 5,305 rounds total.
Assuming he was flying a P-47 with extra ammo option which has 3,400 50cal rounds in AH, 5,305 rounds is about one and a half jugfull of ammunition, with a firing time of total 48 seconds.
In other words, with his gunnery he could have held down the trigger for 32 seconds until he spends the entire ammo load of the P-47 on just one opportunity, and he still wouldn't be able to count "200" hit sprites.
Ofcourse he's lying. Or exaggerating grossly, rather.
He didn't put 200 rounds in that 190. He probably fired 200 rounds. With his 3.77% gunnery, out of those 200 rounds fired he probably landed about only around 7~8.