I am at a loss to figure out what happened this morning. My rifle is a Remington 700 with a TriggerTech trigger chambered in 20x47 Lapua. I was working on a new load. The load was 39grs RL17, CCI 400 primer and 55gr Bergers. This was the starting load recommended to me by someone that has loaded a lot for this calibre. The first shot showed the expected velocity (3800fps) and showed no signs at all of over pressure. (no stiff bolt lift at all, primer signs or ejector marks on the brass). On the second shot, however, the primer was pierced, the velocity was 100fps higher and it broke the sear on the trigger. There was no stiff bolt lift or any other signs of high pressure. The only thing that made me believe that it could be high pressure is the increase in velocity. I use a beam scale and double check every charge so I am doubtful that it was a heavy powder charge. I know that the strength of the firing pin spring or the shape of the firing pin could be the cause of the pierced primer. What I am struggling to figure out though, is whether the broken sear was caused by the reaction of the piercing somehow or if I have 2 separate issues that are somehow not related. I have been reloading for several years and I am very meticulous when it comes to loading for accuracy so I would like to think that I did not overcharge that round. I have definitely loaded some hot loads in the past for a few of my other rifles but I have never had a primer pierced because of it. I have found very little on the forums regarding broken sears in a rifle. Any ideas or advice on what may have happened would be appreciated.
thank you
thank you
