03-13-2022, 05:07 PM
michael1778 Wrote:Thank you.
[...] 1 in 9 twist worries me for longer, heavier hunting bullets like the Nosler 129gr ABLR or the 130 Swift Scirocco.
While I'm sure someone else can offer some advice on the specific bullet weights you mentioned combined with 1:9 twist rate, the thing that made me go with 1:9 for my 24" barrel is because it's what Bill Alexander went with for Alexander Arms 20"-24" barrels. Alexander, I believe, acknowledged that his choice varied from standard wisdom on the topic, but it was based on his testing as he developed the cartridge.
From my limited understanding, the additional muzzle velocity from the longer barrel lengths translates increased RPMs over the same cartridge from the same twist but shorter barrel, and closer RPMs to the same cartridge from the shorter barrel with a faster twist rate. My understanding is admittedly cursory. Google will produce articles on the topic with the right keywords and some sifting through results. (Slightly off topic, any articles about Q's development of the 8.6 Blackout (8.6 Creedmoor) have a good chance to mention some progressive approaches to using twist rate to affect ballistics wound cavity size. Interesting stuff, if you nerd out on ballistics.)
'Cause when we stop and look around us / There is nothing that we need
In a world of persecution / That is burning in its greed
[...]in the grey of the morning / My mind becomes confused
Between the dead and the sleeping / And the road that I must choose
--"Question", Justin Hayward
In a world of persecution / That is burning in its greed
[...]in the grey of the morning / My mind becomes confused
Between the dead and the sleeping / And the road that I must choose
--"Question", Justin Hayward