so the 34s came in today. I tried one with a 460s&w load. Typically I use 42.5 grains of H110 with a large magnum rifle primer behind a 300 grain bullet. To be cautious, I backed off to 40 grains of H110 even for the CCI 34. Good thing I did. The recoil, shockwave, and fireball were at least as big with the 34 primer and 40 grains of H110 as with the large magnum rifle primer and 42.5 grains.

I think the 34s are hotter than even the large rifle magnum primers.