I was looking to load some 160tsx in 7mm rem mag and barnes had 63 grains rl-22 as max. I don't understand it. with 66.5 grains i am still no pressure and get 2865 fps. I have a friend that shoots 70.5 grains and has no pressure signs and that his is best load. why are they so conservative on max loads in the books?

I also noticed that a number of loads in their most recent manual were less than in an earlier manual. I called Barnes and talked with a technician and he told me that the loads in the latest manual were developed under close supervision by their attorneys using strict SAAMI specs. He advised me to use a chronograph and work up loads using my older manual.

When the 7mm rem mag was born many years ago, different brands of rifles had large variations in chambers & throats. In other words, each rifle is different as to what the maximum load will be. You also need to look up the history of the Barnes first all copper bullets. They made much more pressure then the current bullets with the grooves cut in them.