If a 9 will spin a 100 as accurately as it did in my 700V, no doubt an 8 will do just fine with any 140s......there are 3 things to think about.
First let me say I have always been fast twist guy. Yet I think there IS a point of diminishing returns in many things.
1) Increase twists substantially and it can lead to a slight increase in pressure, odds are the fouling will increase slightly, and a Decrease in speed. It all depends on caliber, bullet weight used, case capacity, barrel quality, etc. These are perhaps subtle differences, but let's just say I never had great accuracy 7RM with 140s, EVERY 7RM I have used preferred 150s or higher. That was factory twist, from 9 - 9.5.
Folks who are or have used 8 or 8.5 can tell you........but if you are using an 8 with 140s in a 7/08, I think you will be completely fine. Likely a non-issue. I do not believe you will have any INCREASE in accuracy over a 9......but that's just my .02
Last edited by 65BR; 01/02/20.
