I was shooting 147 grain milsurp in my Mosin-Nagant, which of course is 7.62x54r. Although it can bite, I think I brought a lot of it on myself. With all the new stuff I was being exposed to in the clinic, I think I just neglected the basics of keeping the rifle firmly planted on my shoulder. Had a little trouble with the 2nd stripper clip during one rapid-fire segment, and I think I just got in a little too much of a hurry.
Still, enjoyed the heck out of it, and will keep at it.