Evening fellas, got a problem. Trying to get my friends brand new 300WM Remington ready pronto for Sept moose hunt. Every peice of brass wether new brass or once fired reloads sticks to some degree after firing. Not lifting bolt, just pulling back...some we have had to give gentle whack with a book. Had some spare nickel plated factory rounds and 1 of 3 had very slight tension. Tried new Win and Rem brass. You can see brass is scraped just above the belt(1/8 inch). WE were shooting 78 gns. of H1000 and tried backing off to 75. Only slightly better results. We also tried his once fired brass in my rifle and it also stuck in mine. All rounds loaded easily. Looked in chamber to see if there was a burr and tried to put a bent pick in rear of chamber to try to feel burr but cannot see or feel anything irregular. Double checked OAL and tried backing off to see if pressure from bullet being accidently in lands could have produced high pressures. My thoughts are burr exists that would be much more apt to stop a piece of regular brass than the nickel plated due to hardness. This is a factory rifle.I'm considering trying to hone rear part of chamber as it worked for someone else on another thread. Its almost like the round grows beyond the size of the chamber but that sound kinda rediculous. Also we tried 78-79-75 grains and accuracy is pretty terrible. I got behind the wheel and best is doing 3.5 at 100yards. No brake on this rifle makes me really, really appreciate mine. Any other suggestions?