I bought an Accuracy International rifle from someone here on SH, and it was supposed to be the Small Firing Pin (SFP) version of the short action AXMC. After shooting it for a year or so I decided to try the Lapua 6.5 creedmoor brass which of course has the small rifle primers. I'm getting some interesting results as you can see in the pictures. I learned today from someone at milehighshooting that in this rifle the firing pin protrusion can be adjusted. It may be that it's protruding too much, or it may be that it's the large firing pin version. I measured the firing pin at 2mm diameter (about 0.080 inches). I'd love to hear some thoughts from people that have seen this before or who have experience with this rifle. My impression is that the primers don't show the flattening that I would expect with excessive pressures. This would lead me to believe that it has to do with either the firing pin protruding too much (very likely) or the size of the firing pin (the internet says "maybe").

