Velocity vs twist rate
- Thread starter jesilva
- Start date
XTR
F-TR obssessed shooting junkie
Bryan Litz posted results of 30 cal testing showing that you lose about 1.3 FPS per inch of twist, the difference in a 1:8 vs a 1:12 308 was 12 FPS. Don't think you can see it.
http://bulletin.accurateshooter.com/tag/bryan-litz/
http://bulletin.accurateshooter.com/tag/bryan-litz/
There is an article by Bryan Litz exploring this question. It is on this forum, I believe in the archives of "The Daily Bulletin".. But to basically answer your question, there is very little difference. I think, if memory serves me correctly, it is about a 6f.p.s. loss per 1/2 twist. So you should not be losing more than say 15f.p.s. from a 8 twist as opposed to a 9 twist. But, to be on the safe side, ask Bryan, who is a contributing member of this forum.. He owns "Applied Ballistics" and is a "for real" ballistician!
Thanks.
Yes it does, but pressure makes velocity. I think it about evens out and that is why you see so little difference. Matt
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