I have many decades of firearm experience, but I would still want a weapon master on set to double check me when we were using firearms. However, my focus is drama and cheesy guns are not going to fly. I have an Airsoft M1898 Mauser I used for a World War II clip, I just removed the orange cap. Would be fine for long and medium range, but for up close shots it has cheesy written all over it.
I have a couple of scenes I'm planning where a revolver is used (to show the gun is loaded) and the ammo is visible in the cylinder for close-ups, and we ordered some replica ammunition ($15 bucks for 6 rounds) that fits in a real revolver then made it double safe by dropped a wooden dowl down the barrel (after the actress cocks it while pointed safely away from herself) so the cylinder can't advance.
Gotta be careful, but you also have to deliver the goods. Guns put asses in seats, as they say.