Home Forums Reloading Reloading Software Magnum Primers or Regular?

A long time ago someone here on the 'fire said magnum primers were only needed under 'usual circumstances' with loads exceeding 79 grains of powder.

So I tested that with my 375 H&H and my favorite 270 grain bullet load of 75 gr. R15. Sure enough, I got slightly better, and measurably smaller groups using LR primers than with Magnum primers.

Now if I was in bitter, bitter cold I might swap out the LR primer for something hotter, but now I only use magnum primers in my 400 Jeffery, which uses 82+ gr. of powder.