Cutting back a gain twist you'll loose some of your final twist. It's not even 7.75 now. If it finishes at around 8 you'll cut out some of the heavies.
I load for my 260 and my son in laws 6.5 creed. With RL17. I load the 147 eldm for the 260 and Sierra 142 for the creed. Both shoot very good. My Alliant manual says 41 grain is the top for the 260 with 140 speers and 41.8 is tops for the 140 Speer. I'd start low and work up. I use cci 450's...
That's what I interpreted from longbomer's post. With the help of cody's input Because Even at impact velocities. The rpm numbers are different. With a lower divider the farther you go out.
I guess that's where I was confused. I thought that if a barrel twist was 1:8". That the bullet flew a 1:8". But because flight time was less with higher velocity that was the greater RPM numbers. Man my head hurts.
I'm trying to rap my head around this. If your data says the impact velocity at 500 yds is 2000 fps. Then you load down to where your impact velocity at 100 yds is 2000 fps. Just for bullet expansion test. How is the impact rpm different. I understand rpm formula. Higher muzzle velocity equals...