I've tested the 130, 150, and 180 grain bullets in 2 different b 300 Win Mag rifles. One of them loved all three of these bullets, and the other did not. I also tested the 130 gr. Bullet in a .270, and that gun did not "like" them. All 3 of these rifles are older, lighter, hunting rifles with a 10" twist. The 300 Win Mag rifle that did not like these bullets, instead likes older style lead core bullets. I'm not sure why. Same goes for the .270 rifle. In all three rifles, the best groups were achieved by seating the bullet deeper (about .035" - .050" off the lands). The 2 rifles that did not "like" these bullets shot their best groups with conventional lead-core bullets. The one rifle that liked these bullets shot 1/2" groups when the right powder/seating depth was used.

Accurate and fast in my WSM