I used to have a Trapper, which I sorely regret selling, in 45 Colt. Before I knew anything about the 45 Schofield, I tried timming off 1/4" off some 45 Colt brass and used them in the Trapper to get 10 rds. They fed and cycled without a hitch. Remember that not all Trappers, like anything else we shoot, are going to be the same. It may not work as well out of your's. Only thing to do is to load up some dummy rounds and see how the work, if this is what you want to do to get more rounds in the mag.