Thanks to information posted by Michael Courtney, I decided to try 69g SMK's in my 12 twist 22-250. Hodgdon load data showed 3499 fps mv from a 24" barrel using Superformance with a 70g bullet, so I used that data for my workup. I chose the 40.2g load, which produced a .445" group @ 100 yards and averaged 3579 fps from a 26" barrel. I can't wait to stretch the range with this load and see what it can do!
I have also prepared some test loads with RL-17, but didn't have time to shoot them.
Attached are images of my load workup and my rifle.
Great info, looks like at that velocity you are having no problems stabilizing. This should be a fun load. I shoot the 69 in a 1/10 26 inch .223 with good results on a hot load. Keep us posted.
Will gladly continue to post results as I have them.
According to the information and spreadsheet/calculator posted by Mr. Courtney, a 12 twist is sufficient to stabilize the 69 SMK, even at lower velocities, but that same information also shows that a lower level of stability can reduce bc. When I shoot this load at longer range, I hope to determine whether or not it is stable enough to get the full bc value.
Michael Courtney's research was a real eye opener and an interesting read.