The primers on my 308 load are showing signs of cratering in which the sides of the firing pin indentation rise above the surface of the primer. Normally this would indicate excessive pressure but the load I’m using is Hodgdon’s recommended starting point: 41.0 grains of H4895. I reduced the load to 36.0 grains but the cratering still occurs. At 36.0 grains, the bullet chronographs at 2,381 fps which is well below the 2,551 fps of Hodgdon’s starting load. I thought it could be the Winchester WLR primers but I also use them in my M1 Garand with no sign of cratering whatsoever.
Would appreciate any suggestions you have on what may be causing the cratering.
Would appreciate any suggestions you have on what may be causing the cratering.