I have been shooting htis 7MM WSM for 4 years now and like it plenty. Except, I get cratred primers with nearly any load. Actually I have shot other powders through it long ago but dont remember any cratering issues. I probably didnt even know about it. ANyway, I have been using magpro powder below the max charge most of the time and it doesnt seem to matter. I have reduced some loads to safe minimums and it still craters primers. I am going to try a few with H1000 and some H4350 and see if the results are the same. The accuracy and velocity are right what I want but these cratered primers still leave a question.
I load my 06 to the max with H4350 and as well 243 with the max powder charge and dont get any cratered primers.
I was getting 3300 and change out of a hornady 139 grain sst with 73 grains of the magpro which is less than the max. I reduced the load to 69 grains and was still getting cratered primers. Any ideas?