I have a 375 Rum that I built. Had a donor action and bought a used barrel off here that I had installed. Was working up a load for this years elk season and was getting 1.25-1.75 3 shot groups till I got a .75" group so settled on that with season nearing. My load is 101 gr of R19 and a 260 acubond. I gave the barrel a cleaning and verified my load. Shot a fouler let barrel cool then three more shots back to back. First two .5" third 4" low and to the left. Let barrel cool and shot two more shots back to back, first shot was where it should have been, second was to the right a couple inches? It looked like my scope was sliding in the rings, but I couldn't move it. So I re torqued rings and action screws. Now I get two good shots then a flier, but my cold bore shot is always where is should be. Its a rem 700, hougue stock that has aluminum pillars and barrel is free floated. Barrel is a sporter contour. Scope is a vortex diamondback with vortex rings. I made sure they were both 1". Is barrel getting to hot? I don't want to tear it apart with me scheduled to leave friday, but am pushing trip back due to a wild fire in my unit.