Gain Twist

[Titegroups]

Did the original '58 Remingtons have gain twist rifling?

 

[kaac1221]

Yes, they do. As well as the orig Colts

 

[Dave Rosenthal]

O-K, now educate me please!

Never heard the term before, so what's it mean?

Dave

 

[zimmerstutzen]

a twist that accelerates as it proceeds toward the muzzle.

A normal twist is uniform through out the barrelo length. A gain twist gradually spins faster as the ball/bullet nears the muzzle.

 

[Dave Rosenthal]

That's what I thought it might be, thanks!

I'll have to check the 1860 Army barrel when I clean it to see if it's noticeable.

Thanks again!

Dave

 

[R.M.]

I don't think the modern Colt replicas have it, and only some of the Remmies.
Some claim it works well, others say there's no difference in accuracy compared to the normal barrels.

 

[Dave Rosenthal]

O-K Rob, and thanks!

Dave

 

[poordevil]

The reason was to allow the bullet to grip the rifling at the start without stripping.

 

[Leatherbark]

My Pietta "Shooters" model has the progressive rifling and a silver looking plated trigger guard. Also a hair trigger and windage adjustable front sight like an Uberti...............Plus it'll put a ball through a gnats tail at 25 yards.............Bob

 

[Titegroups]

I read that somewhere and glad someone could verify that. Didn't realize Colt used it too. I read S&W used it in the newer 460 revolvers. May have to get one of those Pietta shooters models someday. Seems pretty high tech for the time period. Thanks.

 

[Titegroups]

Was thinking about why they went with that, a ball has a very minimal bearing surface in contact with the rifling compared to a bullet, and may have had a tendency to strip as it entered the rifling. No patch could be used with the cylinder gap. Must have been tricky to come up with a machine to cut the rifling.

 

[Dphar]

O-K, now educate me please!

Never heard the term before, so what's it mean?

Dave

Twist starts slow. In rifles using cloth patched balls/bullets it would start at perhaps 72" and end at 48.
If used with a picket bullet they might end with a 30-36 twist.
Bullet guns shooting bullets with long bearing surfaces do not work as well with gains in the 2:1 range. According to a friend well versed in this bullet guns such as the 38 shooting heavy bullets (300+ grains) work best with only 1/2" of gain. 15.5 at the breech and 15 or so at the muzzle. The sight gain does not have the front of the long bearing surface twisted faster than the base.
The advantage to the gain is that there is a positive gain to the twist at the muzzle. Rifling guides or methods that allow the twist to have even a slight reverse gain at the muzzle have a bad effect on accuracy. Or so I have read.
I can see where this could have been a problem with old wooden rifling guides and how making them with a positive gain might have cured a problem.

Dan

 

[zimmerstutzen]

gain twist rifling was used even with bullets and a few guns even into the smokeless age.

However, I think it was Harry Pope that figured with the switch from black to smokeless and harder alloy bullets, that gain twist wasn't as accurate and/or created too much pressure. As I recall the early smokeless Carcano's had a gain twist barrel, and weren't as accurate as the later ones with a straight twist.

I don't believe I ever had a gain twist barrel. I do have a couple of rifles with choked bores. The muzzleloader choked bore barrel couldn't get any more accurate unless it had a false muzzle.

It especially makes sense with a pistol, because of the short barrel length and powder charge limitations.

 

[CoyoteJoe]

My Pietta "Shooters" model has the progressive rifling and a silver looking plated trigger guard. Also a hair trigger and windage adjustable front sight like an Uberti...............Plus it'll put a ball through a gnats tail at 25 yards.............Bob

"Progressive rifling" is not the same as "gain twist", although an individual bore could have both. Progressive means a change in groove depth, generally starting out deeper and "progressively" becoming more shallow. It is similar to a choked bore but applied only to the grooves.

 

[Dave Rosenthal]

Thanks Dan :thumbsup:

I never realized how technical these things are considering they're more than 150 years old! (revolvers I mean)

To a single-shot user, these new-fangled revolvers must have been thought of as zip guns :haha: .

Dave

 

[Leatherbark]

My Pietta "Shooters" model has the progressive rifling and a silver looking plated trigger guard. Also a hair trigger and windage adjustable front sight like an Uberti...............Plus it'll put a ball through a gnats tail at 25 yards.............Bob

"Progressive rifling" is not the same as "gain twist", although an individual bore could have both. Progressive means a change in groove depth, generally starting out deeper and "progressively" becoming more shallow. It is similar to a choked bore but applied only to the grooves.

I just realized that also. I wonder if my Shooters model has progressive or gain rifling. seems like it was advertised with one or the other.........Cant tell from looking in the bore..Sure does shoot good, but even a .457 ball seems too small for the cylinder..............Bob

 

[Titegroups]

Dixie sells that model and lists it as Progressive, 1:30 twist, .008 deep, 5 lands and 5 grooves. I wonder if you could see anything like reduced rifling depth by looking down the bore?