seems to only be on the left side of the rotating turret

third person shows it firing to the side, though, weirdly

I tried it here, and it seems to work, both with and without ACE.

Try to run

[player] spawn BIS_fnc_traceBullets;

That should trace the shots, see if any of them go through.

going to try with only cup mods now

some still go through with only cup but not as many

maybe the viewing hole is in a different position to the turret?

not sure what's causing it. seems like the gun is firing in a different place to what's being aimed at

could it be the porthole view is different to the gun being fired so they're missing?

try the royal saharani orlando tank with a handful of mods with the bullet tracer on and randomly shoot at it on the left side of the turret, about 10 rounds. see if you get anything

can you post a screenshot ? the royal saharani orlando seems to be worse

Yeah, even with only CUP mods installed the machine gun bullets whizz through parts of the left side of the M1A1 tank turret as if it wasn't there, even with [player] spawn BIS_fnc_traceBullets; on.

CUP bug. Also true for the Cold War Crisis mod.

Yeah, I just did a clean install and still persisting if you turn on tracebullets and shoot areas of the left side of the turret (forgot password to old account).

Might be an issue with a non-convex component. I need to re-install the Diag binary to see if that gives a hint