There may be a cleaning problem, but how about the ammo? I would clean the gun, then try another ammo type, preferable good, new U.S. factory. Remember that the primer indent in a dud primer is never as deep as it appears on a fired case. (The primer metal flowing back around the firing pin makes the indent appear deeper than it is.)
With the renewed demand for cheap ammo, importers are scrounging the world for ammo without caring about whether it is any good or not. WWII U.S. GI .45 ammo is being sold without the buyer being told that it is corrosive as all getout. I wonder how many barrels will be ruined.