What is "ratchet" rifling?

[Skychief]

 

[Birddog6]

If memory serves me correctly   (it seldom does) the edge of the land the ball will ride against because of the twist pressure  as it comes out will be sharp & the other side of the rifling that will not have the twist pressure against is rounded or beveled......  How that relates to a ratchet, I don't know.    Unless they are thinking it simulates slip one way & catch the edge of the rifling the other way ?  

Could be wrong. but that is what I was thinking it was.  

Keith Lisle

[Ken G]

What Keith said. 

[whitebear]

Is there an advantage to this type of rifling, more accurate, easier to clean?

[Don Getz]

Actually, none of the descriptions above really show what some call "ratchet" rifling.    "Ratchet" rifling, or what some people call it, is really a mistake.   It happens when the top of the rifling cutter is ground on an angle and it will cut the
groove deeper on one side than the other, thus giving the illusion of "ratchet" rifling.  In order to produce rifling similar
to the ratchet rifling shown above, you would have to "re-cut" the tops of the lands, I don't know of any barrel maker
doing this.   Of course it could be done, I just don't see any advantage in doing it..........Don

[Roger B]

Mine was done by Hoyt & was intentional.  I suspect he did it to prevent "stripping" of the ball in the gain  gain twist barrel. I didn't shoot the rifle much before selling it, so I'm not sure how successful it was.  It is kind of a cool concept though!  We have so many accurate barrels these days that any advantage would have to be nearly academic.
Roger B 

[Clowdis]

Shilen produces barrels with the ratchet rifling as described. It supposedly gives less deformity to the bullet and makes the barrel easier to clean. In point of fact it is no better or worse than any other type of rifling they produce as I understand it from shooters who have tried it. Another common type of rifling being produced today is the 5R as shown in Ken's illustration although it is more similar to the hybrid rifling profile. Once again it is supposed to produce less stress to the copper jackets on modern bullets. Everything old is new again!

[LynnC]

Ratchet rifling was pretty common during the CW.    Many Confederate cannon and British imports like Armstongs and Blakeleys used ratchet rifling.  It was a time of experimentation in the 1850s and early 60s, the theory being that only one side of the groove did any work as the projectile exited.  I have no idea when it was first used.  Must not be any better rifling system than any other as we don't see it much used today........Lynn

[ken]

Ultrahigh barrles made in Japan used that type of rifling.Works OK not top Quality by any strech.

[Hawken62_flint]

I agree with the previous posts about what it is, but wanted to add that I am currently building a .32 caliber flint with a J. T. McCartney (West Virginia barrel maker - mid 70's to around '80) ratched rifled barrel, and the rifling looks just like the picture of it in the previous post.

[Steve Bookout]

I have often cut this type of rifling because my cutter bit was not inlet "square with the world" into the cutter head.  I have found no pluses or minuses when shooting such a made barrel.  Cheers, Bookie

[FL-Flintlock]

Is Daryl okay?  Thought he'd have chimed in on this one already.  Ratchet rifling was used here and there as other have pointed out and it can be a great benefit in certain applications.  It's absolutely necessary in the Paradox guns because you're trying to catch and put spin on a projo that already trucking along at 1200-1400 fps.  The name escapes me at the moment but there was a company in Taiwan producing pneumatic pellet rifles with ratchet rifling, far less deformation of the pellets produced exceptional accuracy.   Several of the Burton, Lee & Martini-Henry rifles used ratchet rifling.