My Win model 70, .300 Mag shot Barnes TSX 180 grain boat tails wildly and all over the place with IMR 4350 and 4831. Barnes suggested the 200 grain TSX Flatbase and it shoots them very accurately. I've been using 66.5 grains of IMR 4831. However, a Safari hunter recommended RL 22 and says he finds it cleaner and more accurate. Another handloader said he liked VihtaVuori Oy powder and it gave him better performance (I do not remember which, probably N160 or N165).
After seeing the effects of Barnes on a lot of animals, I want to stick with them. Can anyone else tell me their results with VihtaVuori Oy or RL 22 powder? Thanks.