I've reloaded for a long time and never had this problem with a Smith & Wesson 686. I loaded some Falcon brand semi wad cutter 158 grain with 4.1 gr of HP38, Starline 357 case with CCI primer. It took me 2 hours to remove lead from the barrel throat after 50 rounds. The lead came out in thin slivers. The bullets mic out at .358 which is the norm for a lead bullet in 38/357 loads. What can I be doing wrong?