Gain Twist Yay or Nay

[Aaron N]

So talking to my barrel guy he was suggesting using a gain twist in my Swede and 7x57 barrels.

are there any pros and cons?

 

[khesser]

I had one rifle with a gain twist barrel. Can’t say it shot better than other custom barrels I get from Bartlein or that it had improved barrel life. This was on a 6.5 Creedmoor. I don’t think there are any noticeable positives or negatives.

 

[Bob Nelson 35Whelen]

So talking to my barrel guy he was suggesting using a gain twist in my Swede and 7x57 barrels.

are there any pros and cons?

@Aaron N
Gain twist rifling has been around for a long time. The Italian carcano in 6.5x52 used it and a few manufacturers have used it over the years.
A mate had a sweede 6.5x55 built and the smith accidentally made a gain twist barrel instead of a normal. The mate had it fitted and gave it ago. Turned out to be the most accurate rifle he has ever used. Gain twist has its advantages but it has to be done PROPERLY.
The spin starts off slow and gets faster towards the muzzle end. Supposed to be easier in the projectile as well as reduce pressure as the projectile has a more gradual rotation until the muzzle. I can neither confirm or deny this as it's above my pay grade and mental capacity.
Try it and let us all know.
Bob

 

[Inline6]

I don't think it is required for the two cartridges you are building. Have used them in the past to try to make it easier on the bullets (pushing them hard).

I did not see anything negative. They all shot very accurately. That said, I like keeping things simple. I would run a fast twist and be done with it. If that is your only option for a faster twist or he has that on hand and keeps you from waiting a year for a blank. I would not hesitate.

 

[Aaron N]

Is it possible it would help prevent a 6.5x68 from being a barrel burner? From what I’m reading it’s easier on throats?

 

[khesser]

No. It won’t reduce barrel wear. I have found slower burning powders will help reduce barrel wear but not much else.

 

[Ontario Hunter]

Interesting thread. Thanks for posting. I'm learning something new and did not think it possible. Was sure I knew it all. So I was wrong. Another first.