Home Forums Hunting & Shooting Ask The Gunwriters Faster barrel twist and barrel life?

Does a faster twist barrel have a shorter life compared to a slow twist barrel, all else being the same?

Never been able to see a difference.

No. Why would you think otherwise?

Internet gossip!

Assuming the use of heavy for caliber bullets in the fast twist barrel, I'd expect slightly longer barrel life. Reason being heavier bullets use less powder, and it's the hot gasses from the burning powder that wears out a barrel.

All things being equal ( bullet, powder, weight charge), in a faster twist the bullet would have longer travel in the same length barrel. Much more, no. I doubt you would ever notice the difference in the life of the barrel as the thoat would be toast first I think, which shouldn't be affected by twist at all. Just my unlearned opinion.

Anything that increases the heat absorbed by the throat decreases barrel life.

Fast twists increase the force necessary to engrave the bullet, increasing the bullet's dwell time in the throat, increasing the amount of heat absorbed by the throat.

No.

Even if it did, it'd be worth it.

Yes, they do if you shoot heavy for caliber bullets.
See Kevin Thomas's response in this Accurate Shooter thread.
Kevin was with Sierra Bullets and is now with Lapua.

Barrel life

That link is a very interesting thread. In the end it's about dwell time, and faster twist is one (of several) factors that can increase the dwell time.

Casey

Retarded.



Dave

?............

Does that mean you have a question?



Dave

If memory is correct i think that was the findings with the Barnes Quick Twist chamberings. They were using very heavy for caliber bullets. Also, so old that the findings may be outdated. Especially with newer powders.

Heavier bullets generally have longer bearing surfaces... more wear would be a theory rather than twist issues.

Kevin and I came to different conclusions on a few things over the years. I"m sure he probably is more or less correct, but moly was one thing that just worked for what I was doing and it did give more barrel life.

The barrel life comparison I can give goes from 9 twist button to 6.5 twist button, including 8s, fractional 7s and 7s.

If they were all built and rifled the same, then there was no appreciable difference. In 223 with heavy bullets could die around 3000 rounds, could go to about 4500 or so just depending.

Would end up swapping tubes at 3500 as insurance. IIRC AMU Ft Benning did it at 2500 as insurance.

There are so many variances in measuring such things that such things are immeasurable.

There is ZERO concern in reducing barrel life due to twist.



Clark

Exactly! I can't believe the none factors that people focus on.

They're nerds. It's what they do. Grin...

Happy New Year.



Travis

Instead, I'll make it a statement.

A heavier bullet starts slower, extending the amount of time the powder heats/flames the throat. Faster twist slows down any bullet regardless of weight more than a slow twist will. Also, heavier bullets are usually used in conjunction with slower burning powders, further extending the time the heat acts on the throat.

And of course there are other factors that can contribute to throat erosion such as angle of bottleneck in the brass, neck length, etc.

I've had the opportunity to look down enough borescopes to see that the throat area is what takes the beating, not the lands further down the barrel. The throat will be long gone before we can ever wear out the lands.

Yhou're right, twist rate probably is not very significant taken alone, it's all the factors taken together.

Casey