Gain twist rifling what is it, the purpose,

[Artificer]

I have a notion the Remington NMA was gain twist. OTOH just because something is in my head does not make it true :surrender:

I was thinking the same thing while reading through the thread. The problem is that while I have done trigger jobs on original Remington NMA's and some other work, I never actually checked the bores to see if they were gain twist.

I do know that in International Shooting, at least through the 1990's, many world competitors always asked if the U.S. Team had any original Remington Revolvers for sale, they were that highly regarded in that competition.

Gus

 

[RokonTB]

I have read that the GainTwist Barrels were supposed to foul less near the breach where the fouling is the greatest.
Ron

 

[M. De Land]

On another forum we are discussing gain twist as well and one poster pointed out that the big new Smith and Wesson revolvers chambered in 480 and 500 magnum cartridges both employ gain twist to help counteract the tremendous torque they generate.
The gain begins at 1 in 100 up to 1 in 20 according to the magazine article the poster was sighting.
They advertize that the gain substantially lessons peak torque pressure to the shooters hand.

 

[ResearchPress]

William Metford's long range match rifles (built by George Gibbs) introduced in 1865 had gain twist rifling. Metford's rifling was patented and according to his observations "the law which should govern the rotation of a bullet must be this, that the growth of the rotating or tortional movement should be exactly proportional to the growth of the linear movement of the bullet. Thus the tortional force will be uniform throughout the discharge."

Metford also cited reduced liklihood of the paper patched bullet stripping the rifling with gain twist, and the shearing effect on the patch aided it being shed from the bullet as it left the barrel.

Irrespective of the merits of his theory Metford barrels were used with great success in long range competition from their introduction and through the black powder cartrdge period. Besides Gibbs, Westley Richards also made rifles with Metford barrels.

In the 1865/66 2000 yard trials the specially designed Gibbs-Metford rifles were the only ones that had any success (ie. able to hit the target!).

Kerr rifles (which had some limited use by sharpshooters in the Civil War and much use by riflemen on the target ranges of GB) also had gain twist rifling.

David

 

[Rifleman1776]

Irrespective of the merits of his theory

And...there lies the reason why those of us who love guns and shooting will never stop discussing and debate what is 'best' in any aspect of this game. Those long range shooters are finicky and obsessed with scores of details. Who can really say which bit of minutiae actually contributes to their success? Or failure.

 

[galamb]

There is the ability for anyone here, who wants to do some first hand experiments, to try a gain twist for themselves.

Colerain Barrels is currently equipped to cut a gain twist barrel.

Yes, it is special order and would probably take a while to get it, but they can make one for you.

They will (typically) make a 42" barrel with a gain twist going from 1:96 (breech) to 1:48 (muzzle).

They can make with a different twist (special, special order) or vary the barrel length - although my inquiry (a couple years back now), was told that wouldn't effect the twist rate - it would just (compact) it into the shorter barrel length - so would go from 1:96 to 1:48 is 32" instead of 42" (or whatever).

At least that was how "their version" of gain twist would work.

I no longer remember the price quote that I got but do remember that it (a straight barrel) was somewhere "north" of the cost of a radius groove swamped barrel from Rice (which I did order after investigating the gain twist, and the Rice cost me "to my door", about 350 Canuck bucks when the dollar was at par).

Given that I hunt my rifles and only need minute of Bambi "extreme accuracy" is pretty low on my requirement list for a barrel. Profile and caliber are the driving factors "for me".

I am intrigued by the gain twist because it's sorta unique, but from my limited experience with it I'm not willing to pay a super premium for it and I don't feel that the "average shooter" would ever see any benefit from it.

Most of us can shoot no where as accurately as our current barrels can to start with.

 

[curator]

Gain-twist rifling arrived along with the "picket ball" or early conical muzzle loading bullet. The picket ball or "sugar-loaf" bullet was 1 1/2 times as long as its diameter. It also had a rounded base and tapered sides. Read Ned Roberts' "Muzzle loading caplock rifle" for more information about this step in rifle evolution.

It was quickly learned that picket balls needed more spin from the slow, round ball twist rifling but their very short bearing surface would allow them to strip out of the rifling if pushed too fast. Barrel/rifle makers came up with the gain twist which was found to work equally well with either PRB or conical.

Sam Colt used gain-twist rifling for this reason as well, advertising the ability to shoot either round ball or conicals accurately from the same gun. Army testing of the Colt 1849 Army revolver shooting a 220 grain conical bullet had better accuracy and equal energy at 100 yards compared to the issue 1841 .54 caliber rifle firing a patched round ball.

 

[Loyalist Dave]

Gain twist, like so many ideas in the history of firearms was just that, an idea. If the idea really had proven to have benefit we would see a lot more barrels like that. But it proved to be just another historical oddity and fell out of style.

Well somebody needs to tell the US Army Ordinance Department and Smith & Wesson....

The reason why they aren't all over the place with BP barrels is we don't get the velocities needed to really find an advantage with the gain-twist...especially with modern steel and modern machining in our barrels.

However, several successful models of 20mm cannon as well as the S&W 460 "extreme velocity" handgun do use gain-twist. So folks may hear of its modern application, then discover the idea is pretty old, and wonder why it's not applied in the traditional guns more often. Basically...if your not trying to launch a 300 grain, conical projectile at 2000 fps...you aren't going to find much if any advantage. If you're using a patched, round ball, probably no advantage even if it was going that fast.

LD

 

[M. De Land]

A point brought to my attention on another forum today made the light come on as to why Pope always used a left hand gain twist for his personal use, and I totally missed it!
The center of rotation is the center of the barrels bore and most any comb on a stock is lower than the bores center so a LH twist, making a RH torque rotation would be putting the pressure against a RH shooters cheek, because it is on the bottom side of the center of torque rotation.