I see pacnor makes a 1-4" 5 groove 308 barrel. what would one use such a super fast twist barrel for?

Super long bullets?
Sounds like more of a technology display than a useful item, although I could see uses for a 1/6 twist .224 barrel.

If this sounds less than intelligent, I apologize as I couldn’t think of a way to rephrase the question. If someone knows, “is there a point where an ultra fast twist rate with relating abnormally long bullet length become inefficient compared to a less fast twist rate with relating less long bullet length?”

Jim

I could possibly be for longer range accuracy in the new subsonic bullets that are very quiet for urban police work. these guns have very long silencers, and im told are used for guard dogs at crackhouses before a raid for instance.. dave

quote:

Originally posted by capoward:
If this sounds less than intelligent, I apologize as I couldn’t think of a way to rephrase the question. If someone knows, “is there a point where an ultra fast twist rate with relating abnormally long bullet length become inefficient compared to a less fast twist rate with relating less long bullet length?”

Jim

The advantage of the ultra long bullets is ultra high bc, which helps long range performance. Of course the downside of heavy for caliber bullets is the loss of muzzle velocity for a given case capaicity. But, if you're starting out with a very large case, you can bump the velocity back up. But when you burn alot of powder for a given bore, the barrel gets burned out pretty quickly.

I see this is a very specialized barrel, or one for experimentors

Sounds like it may have been for the 300 Whisper or similar subsonic cartridge. The original bullet for the Whisper was the 240 gr Sierra MK. That is a terribly long bullet to stabilize at subsonic velocities. The goal was to have it just barely stable enough to be accurate and tumble on impact. The tumbling makes up for lack of expansion and makes a very lethal wound channel if you want to hunt with a Whisper.