I've been shooting box ammo in my Tikka T3X tac 6.5 CM and have actually had some good results out to 500 yds. But my buddy's benchrest 6.5 rifle is a tack driver but he's never had it out past 500. Being a really good benchrest competitor he is very picky about everything and his results prove that. His combo is Sierra 140gn bullets and Alliant Reloader 15. Same for his 308 that is a laser. I'm an experienced pistol reloader and thinking about reloading some 6.5. My question is does anyone know how this powder holds up out to 1000 yds & beyond? I trust his guidance but I'm just looking at all the options out there.