While I don't shoot an optic, I found an excellent CO2 BB pistol to practice in my basement with. It is not especially accurate so I shoot at paper plates on boxes at about 20 ft. It is a very good replica with a functioning slide, functioning safety/decocker, and the replaceable magazine house 18 BBs and the gas cylinder.
https://www.pyramydair.com/product/b...-pistol?m=3659