Gain Twist Barrel

[MikeChapin]

I was out sighting in my latest rifle next to a fella at the range. He was a retired gunsmith. We got to talking about muzzleloaders and he mentioned he had an original Hawkin that he would like to shoot. He said the gun was about a .46 caliber half stock that looked like it had been converted from flint. He wanted to freshen the barrel but had found that it had a gain twist and did not have the equipment to do the job without screwing it up.

My curiosity was roused though. Does anyone here know anyone who puts in a gain twist on a barrel?

 

Ya there is a few of us that but gain in them. In the group that I hang my hat there is 3 or 4 benches that do gain. There is someone in Mazzel blast? that does it.
David

 

[WRussell]

I have a couple of Queen Anne turn off barrel pistols in the works, and plan to put gain twist in the barrels.

I have an original by Clemmes whose barrel is ringed (more like bulged) and bent (I'd guess from muzzle-loading it). I've started a couple of new barrels for it (reproducing the thread was fun) and may put gain twist in them also.

 

I read in some article (might have been Muzzle Blasts - can't remember at this moment) that the practical advantages to gain rifling were outweighed by the cost, which is why it did not "gain" more popularity :crackup:. I don't know if they did it on all models, but my original Colt 1860 Army has gain rifling. I have fired it but can't tell any appreciable difference in accuracy over a replica with regular rifling.

 

[fho]

Yes, on a Harry Pope style rifling bench.
Olie :m2c:

 

[fatboy]

Bobby Hoyt does this , 2 friends have had these done they seem to shoot well at long distance 150and 200yds is were I think this shines

 

[susie s]

I have an original that my Dad fixed up to shoot at the nationals at the time there was really no manufactured ones available yet. Since it was already altered, I had it re-bored and the fellow that did it re-bored it in a gain twist-why, I have no idea. I didn't ask him to do it, but he seemed really pleased with himself and that it was really a good thing! Pope used that system. Anyway, I was talking to some guys on the line who shoot the gain twist about it this spring at the nationals and they said that rifles having the gain twist were really finicky about ball and patch size and load. Since the rifle is pre-civil war, we haven't really shot it that much to establish the correct load for it. We shoot it for pleasure rather than for competiton. My son wants to work with it if he ever gets the time. The guys said once you find the right combination, it is very accurate. The guy's name who bored it was MacLamore-don't even know if he's still alive! Susie

 

[BLAHMAN]

I got a little short barreled rifle that has gain twist in it, but I can't remember how fast it increased.

The only problem I see with gain twist is when you use a tapered barrel, or even a swamped barrel, and the barrel is put in backwards!

Seen that happen a few times....well, the guy who did this, his rifle doesn't go BOOM it goes MOOB.

Scares the manure outa cows! :haha:

 

[SimonKenton]

What exactly IS gain twist and what is it good for?

-Ray :huh:

 

[WRussell]

Gain twist starts out slow and gets tighter as you head for the muzzle. If you start out with a really fast twist, the ball is likely to just shed the part in the grooves and go down the barrel with no spin. Gain twist lets the ball start spinning at a bearable rate, and speed up as it goes so you can get a faster spin rate than otherwise.

 

[mule ear]

Caveat - I know very little about gain twists and I have never experienced or been around a MOOB, although I expect it would scare the C--- out of ME, to say nothing about the cows. :redface:

One reason to use it has been mentioned. I have heard another reason/theory to use a gain twist is - increasing rate of twist may actually offer more resistance to the ball at the muzzle at a time when the pressure of the burning powder would normally be dropping off. The pressure of the powder is said to be maintained uniformly throughout the length of the bore. This is said to increase/improve the efficiency of the powder charge, and the net effect is said to give a slightly higher velosity and more stable rate of spin to the projectile. Can anyone comment on this observation/theory???? Afterall, Harry Pope couldn't have been all that wrong!!!! He may not have been able to explain it either, but his results spoke for themselves.

 

[WRussell]

Higher velocity? I like that idea. Another justification for me to fiddle around with doing gain twist rifling.

 

[Zonie]

Seems like 5 or 10 years ago, there was a barrel company called "Gain Twist" that made muzzleloading barrels with this style of rifling.
I think they went under because I haven't seen their ad's, (Or Orian's) for a few years.

 

[jimbo15563]

Zonie,

Somebody sent me a PM about Orion.

Jimbo, I located another barrel maker near Kalispell that knew Jerry Cunningham. He said that Jerry developed mental problems after his wife left him. Went out of buisness after that. That's all I could come up with.

Jimbo

 

[Zonie]

Sorry to hear about that sort of thing happening to anyone.
The mental problems that is, not necessarily the wife leaving.

 

[mule ear]

W - please re-read my caveat; I ain't no authority. I may be guilty of perpetuating rumors, tho. I'm only repeating what I heard once. I'm not at all sure about the velosity thing. Rumor, speculation, and theory aren't the same thing as reality. The book on Pope's Barrels would be a good start for accurate technical info.

With the scarcity of commercial suppliers and several books on the market about how to make a rifling machine, a motivated and creative individual could make his own rifling machine to cut gain twists. :hmm:

Best of Luck!!!

 

[bpbrs]

I understood gain twist rifling was for slug guns and not as prefered on RB.
Think about it, you have a fast twist at the muzzle what will it do to a patch.

 

[Zonie]

As I understand gain twists, the twist at the muzzle is the same as a regular barrel (like 1:60 or 1:48).

The twist at the breech is something like 1:150 or slower. As the ball or bullet moves thru the barrel towards the muzzle, the rate of twist increases to the final 1:60 or whatever.

As Newtons Law says, things like to stay the way they are and resist change. As the ball is not rotating before it's fired, with a regular twist barrel, it has to develop it's full rotational speed almost instantly. This can make the bullet or patched ball slip or skip in the rifleing.

With a gain twist, its rotation starts off slower and its rotation is (slowly?) accelerated to the final speed as it moves down the barrel and reaches the muzzle.
This was supposed to keep the bullet or patched ball from skipping over the rifleing grooves which could improve accuracy.
I haven't heard that it has much if anything to do with increasing the bullet/balls forward velocity, but it might a little. ::

 

[CoyoteJoe]

Numrich arms used to cut gain twist for the same price as uniform twist and Dixie Gun Works used to sell either for $19.95 back in the 70's. I think they were 1-80 at breech and 1-40 at muzzle, while their uniform twist was 1-56.
I used that barrel on the first ML I built and not knowing it I turned it backward. It never shot real great, 2" or so at 50 yards. I discovered my mistake and turned it around and it shot about the same!
I think gain twist is one of those things which seems to make sense but if it actually helped all barrels would be gain twist by now, instead, there are hardly any.
Gun Parts Co. catalog still lists a few of the Numrich Barrels if you want to experiment.
:m2c:

 

[WRussell]

My perception of reality ("What a concept!") is that gain twist is only worth anything on a pistol, when you're fighting a short barrel and want to get a high spin rate.