Charles Daly Model 601 20 Gauge Semi Automatic Shotgun

Charles Daly Model 601 20 Gauge Semi Automatic Shotgun. We picked this gun up from Buds Gun Shop last month and locked the bolt back for 1 week before taking it to the range. First run was great but it started to get progressively worse so we'll give it a good cleaning and lock it back for one more week and see what happens. We sent this gun back twice to get it fixed, but it still only cycles hot loads.