Does anyone here have anything substantive to add to the notion of gain twist? I have been asking around and reading and talking to one barrel maker about it, and there is nothing definitive. Best I can find is that most British BPE gun makers 1850-1900 used gain twist rifling, as well as tapered bores. Charles Lancaster was a big believer in gain twist and he used it in his successful oval bore cannons.
I ask because I am in the beginning stage of building a percussion rifle. Colerain makes gain twist barrels, and they will make one for this project, if asked.
Thanks!

pamtnman,
Give it a try and let us know how it works out.
Mike

Der Ami, august gunmaker Bill Slusser swears by the high quality of Colerain's gain twist barrels. I think several of our flintlocks built on Colerain barrels have gain twist, but I cannot recall. My son's child-size .45 is a tack driver. The real question is not if gain twist works, or not, but if it is possible to create a middle-ground twist rate that serves equally both long conical-type bullets and also for patched round balls.

pamtnman,
That sounds like a good question to test.
Mike

Der Ami, it is a great question, and I am building a rifle to definitively kill critters, so I am trying to get this settled in my mind before we put the barrel in the stock channel. Might be that the builder and I just have go with what we know.

Nothing but the best of luck with the project. I'd consider asking your chosen barrel maker what their favorite barrel configuration is and what specific projectile is matched to it. I'd think middling barrels are already plentiful. I believe if you discuss it with the barrel maker, purely for twist rate, the bullet will only be affected by the final twist of the gain. It may matter if the bullet encounters different affects cause by the gain, and how skillfully the barrel making was executed. There are modern gain twist barrel makers, one more so, that have quite a record of accuracy accomplishment under competition conditions with correctly matched lead bullets. Only thought, again best of luck.

thank you, Craig. Good suggestion, and I appreciate the encouragement

pamtnman,
I am too old to finish the projects I already have and was looking forward to watching you play with gain twist rifling.
Mike

Well let's see how things work out, Mike. I am set on the barrel length and outer dimensions, its caliber, the stock style and wood, the butt plate, trigger guard, trigger and other furniture. This gain twist bit is the last thing, and it is unsettled. Thank you for being supportive!

I'm looking forward to it.
Mike

When determining what rate of twist you need for a particular usage you need to determine, within a small range, what the powder charge will be. Stability is ultimately determined by rpms, not twist rate alone. The heavier the powder charge the higher the velocity, and the higher the velocity the lower twist rate that seems to be needed to stabilize the projectile.
It is tough to find a twist rate that is fast enough for a bullet but slow enough for round balls. Thompson Center tried this decades ago, and sold many thousands of rifles with a 44" twist, AIR. They never won many serious round ball matches, but would shoot decently enough to keep some people happy, with the right charge. They also shot a bullet to minute of lung. Good enough for many deer hunters, but not for serious competition.

IDK how well gain twist would work for a bullet/ball rifle, but it's an interesting concept, and one I've never heard of being tested. My guess would be the shorter the bullet the better it would stabilize it, as with most mid-range twist barrels. Back when I competed with round ball rifles Douglas XX was the barrel to beat, with custom barrels by Ken Bresein and Jim Goodein leading the pack of custom makers.

My best ever barrel is a .45 Douglas XX with a 66" twist, 42" long and 1 1/8" across the flats. I have shot 5/8", 5 shot, 100 yard groups with it with a tight fitting ball/patch combination.

Good luck ...... SRH

Exactly the input I am looking for, THANK YOU Stan.
It stands to reason that a middlin' ground meant to accommodate both round ball and bullets is not real attainable. I do not trust myself enough to arrive at this kind of conclusion on my own. After second-guessing myself into a circle, I really required outside intervention...so I think I will go with bullets and ask the barrel maker to make the twist appropriately tight. This is a .62 percussion rifle, so the bullets will be big and the powder charges really big. What twist rate would you suggest for a bullet-shaped projectile (Minie or Buffalo Bullet style) in a 34 inch barrel?

I'm afraid I can't be of much help there, regrettably. I have never spent much time with bullet, or slug, m/l rifleguns ............ preferring to specialize in getting the most accuracy out of soft lead round balls. Anything I posted that was helpful I gleaned from others along the journey, watching them and asking questions. I'm glad it was of some help.

I would suggest that you speak at length with the barrel maker, providing him with as much detailed info on the bullet type you want to use as possible. They garner much priceless data on such things over the years. Colerain is a well respected name, tho' I've never dealt with them.

Another suggestion would be to go to one of the major m/l websites and do some searches, or ask the question there. It's been my experience that, in most any field you wish to learn more detailed information about, there are those out there that have been there and done that. Their experiences are, again, priceless.

I would note that a long bullet (Buffalo?) in a .62 cal. is going to weigh a good bit, and might require a hefty charge to keep it rocking along stable. Even a .62 cal. roundball will weigh 340+ grs. No big deal if you need that much weight for bigger game, but shooting it a lot off the bench will produce some notable accumulated recoil.

Best wishes, SRH

Stan - all good points, all useful, and all much appreciated. Gain twist is one of those things a gun guy might hear about occasionally, but not really encounter without purposefully looking for it. I did post a query about it on the muzzleloading forum. The responses were pretty helpful, some amazingly so (a barrel maker, a competitive BP shooter, a book worm), but nothing definitive. Like a lot of people who use this site here, I own British double rifles. Those guns are incredibly accurate. The BPE ones all have both gain twist and a tapered bore. We all know that the British sporting rifle makers were tops. They knew what they were doing. It seems like we have to rebuild the British wheel to find out how it turns.
Colerain made the barrels on our other muzzleloading guns, and they are very accurate. I think my son's child-size .45 flintlock has gain twist. It is a tack driver. Gun builder Bill Slusser swears by the gain twist in Colerain barrels, and he says he has been able to get both round balls and bullets/sabots to shoot very well from them.
Your point about the .62 cal round ball is a good point, one I need to remember again and again. I am so searching for raw knockdown power that I am just about to overdo it with this project. The gun is supposed to be for our early season bear and deer season, for bear, elk and deer in places where flintlocks are not required. A round ball is probably enough for all that...

A big round ball can have unbelievable penetration. My biggest is a .54 Leman half-stock. With it's 34" X 1 1/16" Sharon barrel I can utilize some stout charges. I once shot a 200+ lb. buck with it at the lower edge of his white throat patch, facing me. I was in an elevated position at 80 yds. The ball penetrated him ................... lengthwise, and exited under his right hind leg.

Best wishes on your quest, SRH

I had a couple of Thompson Center .50 cal. Hawkins rifles that shot well with both conicals or patched round balls. In fact, the first shot better with swaged patched balls than any conical bullet I tried. I could usually have 5 shots touching at 50-60 yds. Beyond that, the limiting factor was the open sights with a front bead that covered most of a deer's chest at 100 yds. But even at that, I could easily stay well inside 3 inches at 100 yds which is much better than minute of lung. Peep sights were not legal for our flintlock deer hunting, so I made some modifications to make more precise shooting possible, and still remain legal. For some reason, we had to use round balls too, and I remain very impressed with the performance of them on deer. As Stan said, penetration could be very good due to the momentum of a blob of lead. Of course, hitting bone flattened them out nearly like a half dollar, and they would often be found under the hide on the off side of a deer. Actually, penetration will often be better at lower velocity because the soft lead ball doesn't expand as much in flesh.

I had a .69 cal.percussion musket for a time. It was a blast to shoot with round balls and 160 gr. FFG powder. I was probably using much more powder than necessary, but I was young and using the load the guy I bought it from used. The accuracy was not very good, so it went down the road. Recoil was impressive, but it was more of a long shove than a sharp jolt.

Ok..I’m thinking a slow turn for round balls. Keep it simple. Thanks, guys, you have been helpful.
Btw in my .54 flintlock, the standard hunting load is 100 grains FFG. Think that’s too much? The gun prints well with it at distance. I have yet to take an animal with this particular gun. I’ve missed plenty

100 gr. FFg is a good charge for deer, in a .54 ............. I use 120 in mine, but I like complete penetration and exit, if possible. If I ever got the chance to use it for bigger game - elk, moose, grizzly - I'd go to 160. My rifle handles that heavy a charge very well. I use a very tight ball patch combination on the initial load, then slightly looser for reloads, to make reloading quicker.

Best, SRH

All good advice, Stan, thank you. In that vein, it would stand to reason that the hunting charge on the .62 rifle will be around 140-160 grains of FFG. Do you agree? In one of Sam Fadala's 1990s books he had a .62 rifle that he shot, and while I do not now recall the powder charge, in my memory that figure has been stashed away for future reference. Seems logical to me.
PA

That should be close to right, but only testing will prove what it likes best.

Testing is fun. My crossticks gun was tested for load using a 25X Lyman LWBR scope, which was then removed and the sight bar for the Redfield aperture sight was mounted using the same holes the scope bases utilized, leaving no unsightly holes in the top barrel flat.

Brings back memories.

SRH

Gaintwist works, but be sure you are comfortable with the steel alloy that Colerain is using for your barrel. Perhaps that is not an issue, but it may be.

That is cool as heck, Stan. Those would be fantastic memories. At my end, I struggle to hit the bullseye at 75 yards, and I have a great no-flinch followthrough. Maybe that 25X moon telescope could help

Yeah, you know, Brent, I just became aware of this 12L14 alloy issue. Never would have dawned on me that modern day barrel making could involve a steel with questions attached to it. I spent a lot of time today reading up on this, and it does seem that the 12L14 steel is suitable to black powder and not to smokeless. We have Colerain barrels on our flintlocks, and never had an issue. Very accurate, dimensionally correct. It does make me wonder if I should ask Scott at Colerain to make this .62 barrel out of 4140 or some other more rugged steel. The charges in the .62 rifle barrel will be substantial. They will test that steel. Hmmmmmmmmmm

I'd think it's good to be aware, but I think there would be so much more to barrel making and putting it together to become part of a rifle, than just one small part of the whole picture. It's not related the proposed rifle, but there's a well documented single shot rifle that was featured in Precision Shooting magazine and shown on line. It has a cut rifled gain twist barrel made out of rebar. The point being, it was a stunt, but put together with a high level of expertise and seems to have turned out to be quite a shooter. I personally have no plans to commission a custom muzzle loading barrel, but to a large extent I think confidence would come more from experience and reputation. On the surface, 4140 is a no brainer, but there are probably more than a few of those that have blown or not shot very well.

good point; i know of no Colerain barrels rupturing

OK so Scott Keller at Colerain writes in an email today:"I would not recommend 12L14 for smokeless powder, but it is well suited to black powder and in my 30 years here we have heard of no ruptures of Colerain barrels."

It does seem counter-intuitive that a lighter lower velocity load would have better penetration than a load using a heavy charge of black powder. At some point though, with pure lead round balls, the higher velocity expands the ball so much in flesh that sectional density is totally out the window, and penetration is lessened. I noticed that a higher velocity very expanded lead round ball did a lot of damage and dropped deer quickly. But often the flattened ball would be found under the hide on the off side rather than leaving an exit hole. With less than perfect shot placement, having only an entrance hole makes much less of a blood trail, even though there may be massive hemorrhaging internally.

Everything about muzzleloading involves compromise. A lead round ball isn't moving very fast under the best of circumstances. If you try pushing the limits on range, they start dropping rapidly after 125 yards or so, and reducing velocity permits them to drop more at longer ranges. Once you sight in at say 100 yards, try moving the target back to 125, 150, and 175 yards to see the impressive amount of drop. But that's not really a problem in most Pennsylvania woods hunting.

And if you are missing deer with that .54 flintlock, one thing to remember is that a roundball from a muzzloader is not as well stabilized as a bullet from a high velocity rifle. It doesn't take much to deflect a roundball. I've missed a few shots at standing deer when I had a perfect hold and trigger squeeze. In every case, if I looked hard enough, I'd find that I nicked a small branch or sapling between me and the deer. The amount of deflection is much greater if the branch you hit is closer to you than the deer. So pick an opening carefully when shooting in the brush... which is about 90% of the time. This is just part of what makes hunting with a flintlock more of a challenge. For some beginners, half the battle is just getting it to go off, even when it isn't raining. And if you are getting any delay to speak of between pulling the trigger and having the gun go off, then you are doing something wrong. That flintlock ignition delay is an old wives tale. The difference between a flintlock and a percussion is mere milliseconds if you are loading correctly and have a good lock, frizzen, and flint. Any appreciable ignition delay gives too much time for your sights to wander off target.

I agree with what keith just posted about round ball penetration with pure lead balls. If you want better penetration try a 1:20 lead tin alloy. Full penetration on this buck using 90 grains of 2F Swiss, the hardened ball hit at the base of the neck where it joins the right shoulder and exited the left rear leg. This rifle is a 14 bore belted ball percussion gun by Wm Moore. Conventional wisdom says it should not shoot, twist rate is 1:32 but it shoots just fine.

When I hunted with a .45 flintlock, it took a while, like ten years, to realize that most of my misses were in fact hits, and that following up the deer was the only way to determine what happened. The only two deer I brought to hand with a flintlock were both killed with that .45, and each had a story associated with it.
The .54 has only been fired at deer a few times, and they were long shots, around 100 yards or farther. This is because I tend to be the "dog" or driver pushing deer to the standers, and they get the close shots. Usually I am shooting at an old doe who peeled off from the herd and went sideways, or starting back against the drive.
Ignition and timing are not an issue with this gun. Bill Slusser re-worked the Chambers Siler lock and made it fire instantaneously.
Come to think of it, I do not think I have ever tried to shoot at a target beyond 100 yards with any flintlock....it is worth a try, just as you say, to get a feel for the drop. Just in case there's a Hail Mary to be made on the last day of a long cold season.
Thanks again for all the great advice and help!

I have a hexagonal very heavy barreled percussion rifle with a false muzzle. I see these sometimes called target or sniper rifles. The barrel is stamped "gain twist" and the locks are Golcher. The barrel appears reused from another gun. Also, stamped on the gun is Roth, who was a gunmaker in I think Pennsylvania, and later a principle of Wilkes Barre Gun Co., along with maybe Parry, Tonks , and others. I really have nothing to add except the stamped "gain twist". The gun has a set trigger.

So how did the gain twist work out