Indeed, I've incorporated a bit of the Panther F-type．@GeneralPatrick2

this is a nice looking tank gun, is good and well made, i might be wrong but i think it's the gun and mantlet from the Panther F, which is a sucky version of the Panther, i suppose you chose the Panther F rather than the more iconic Tiger or Panzer IV because the gun doesn't have a muzzle brake?? i'd think it'd be difficult to model a muzzle brake so that's why i'm assuming as such
or maybe you just really like that version of the panther

@Flash0of0green yeah modern tank guns are smoothbore but this is definitely not a modern tank gun, it's a WW2 era tank gun as indicative of the rifled nature and the lack of, as you said, a bore evacuator, and also because it's from a panther F

Don't worry about the details, gentlemen.@Flash0of0green

something i find Strang is the riffling on this tank gun. there is no spiral so the riffling generates no spin. also the fact that it even has riffling is strange because most modern tank guns are smooth bore as to not affect there more exotic ammo types. Armor-piercing fin-stabilized discarding sabot rounds (APFSD), High explosive squash head (HESH), High explosive anti tank (HEAT), High explosive (HE) are normally negatively affected by riffling in a tank barrel. over all its a nice gun.
P.S.
another thing that screams "this is not a modern tank gun" is the absence of a Bore evacuator witch are seen on a number of modern tank guns as well as a number of cold war era tank guns.