Purchased CVA Optima a couple years ago. Info on line said "designed for loose powder", but mine shot pellets fine. My brother had same gun, and his would only fire about 50% with pellets but fine with loose powder.
A few months back I read that CVA had a new breech plug for the gun that was designed for use with either pellet or loose. I contacted CVA and they sent the new plug out free of charge. Unfortunately, I haven't shot the gun since getting it.