doublegunshop.com - home Forums General Discussion Double Rifles, Paradox Guns & Gauge Rifles @ doublegunshop.com Gain Twist...does it work

....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.

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

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

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.

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.

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.


Wow, Steve, that is a heck of a fine picture, thank you for sharing it. In every way. Nice mule deer, great original British sporting rifle...nice going. Send it in to DGJ. One thing about those British sporting arms from the 1850s-1890s is that they did all kinds of things that conventional wisdom and maybe physics said they shouldn't do. As you might remember (you sent me an early Lancaster bullet to study), I have aggregated a bunch of British double rifles in BPE and early nitro, and I have been experimenting for four years with every kind of mix of powder, wadding, and bullet alloy in each. Basically re-creating the wheel, but in terms I can understand and apply. This afternoon was another experimentation with a .450 BPE, comparing modern greased felt wads to Dacron, each over a Walter's vegetable fiber wad, and a mere two-grain increase in Olde Eynsford 1.5FG. Dacron wins again, hands-down, guessing because of powder compression. But the Brits used grease felt and "greased cloth" wads over the powder in their cartridges, some of them pretty thick, like 1/4", as opposed to the 1/16" and 1/8" thick felt wads and 0.030"- 0.060" fiber wads we mostly use today. And in fact, the two grains increase in charge actually meant something to the gun. Surprised me. I really do not know much! Nice to have help here. Thanks, guys!