Barrel Twist Rate Preference

[Bent Sight]

What is your barrel twist preference and why? Do you prefer a 1:48 twist barrel? Do you prefer a 1:66 twist barrel? Why do you prefer one over the other? Which twist rate is more widely preferred in the muzzle loading community?

 

[Walkingeagle]

Well...
I have a older GM 1” IBS .54 cal percussion that shoots exceptionally well with a .530 rb, .018” pillow tick patch and 110gr of 2fg. Its 1:70 twist.
Then I have a .50 GPR that shoots deadly accurate with both 50gr and 90gr 3fg at 1:60 twist.
Then I have a TC .54 Renegade which will shoot the lights out with PRB and 90gr 3fg at 1:48 twist.
I have a .50 GPH that loves 90gr Pyro P and 370gr Maxiball at 1:32 twist.
Then there is my Isaac Haines .50 swamped Rice barrel, which I believe is 1:66 twist and just loves 60gr 2fg and prb.
So.. I dont know how to answer your question.
Walk

 

[bang]

As long as it's not faster than 1:48 a load can be worked for a PRB. With good accuracy.

 

[ASMman]

Hello Bent Sight,

Twist Rate depends on what you are planning on shooting.
For a Round Ball in say a .50 caliber, 1:60 to 1:70 is probably the best.
I believe Thompson Center, with their 1:48, was a compromise for either
Round Ball or their Maxi Ball conical.

AntiqueSledMan.

 

[dave951]

Hello Bent Sight,

Twist Rate depends on what you are planning on shooting.
For a Round Ball in say a .50 caliber, 1:60 to 1:70 is probably the best.
I believe Thompson Center, with their 1:48, was a compromise for either
Round Ball or their Maxi Ball conical.

AntiqueSledMan.

What he said. It really depends on what bullet and type of shooting you want to do. Since I shoot mainly Civil War era guns a slow twist with shallow rifling is my preference for minies.

 

[Grenadier1758]

Rather than twist rate or in consideration with twist rate, look at the width of the lands to the width of the grooves and the depth of the grooves. You want the lands to be equal to or less than the groove width. You want groove depth to be 0.010" to 0.012" deep (square bottom) or 0.014" to 0.016" for radiused grooved barrels to properly hold the patch and contain the fouling between shots. Great performance can be obtained with twist rates from 1 in 48" to 1 in 60".

Good consideration of load development will result in excellent accuracy in jaeger style rifles with twists in the one turn in the barrel length (1 in 28).

Rifles built by Jake and Sam Hawken used the 1 in 48" twist rate and excellent accuracy has been recorded with their rifles. They used 0.010" or slightly deeper groove depth.

So, whether it is 1 in 48, 1 in 60, 1 in 66 or 1 in 70, pay close attention to groove depth and land width.

 

[Rifleman1776]

In museums with good nomenclature shown, the 1:48" is far and away the most common among ordinal rifles. I have long preferred it but my thinking has been changing lately. Oddly, I have forgotten the twist rate on my very accurate target rifle. I've had it so long I just forgot. But, I know what ball/patch/charge combo it likes and is very accurate with that. Numbers don't matter, results do. That said, I simply DO NOT like the 1/72" twist. I had a .54 flinter that required charges north of 100 grains. I never worked up the most accurate load since the recoil past 80 grains was just too uncomfortable for happy shooting for me.

 

[user 43911]

Hello Bent Sight,

Twist Rate depends on what you are planning on shooting.
For a Round Ball in say a .50 caliber, 1:60 to 1:70 is probably the best.
I believe Thompson Center, with their 1:48, was a compromise for either
Round Ball or their Maxi Ball conical.

AntiqueSledMan.

There's the term compromise again with reference to 1 in 48 twist, what should be stated is 1 in 48 twist has the benefit of stabilizing some conical/minie's . 1 in 48 was used for round ball before conical bullets.

 

[user 43911]

As long as it's not faster than 1:48 a load can be worked for a PRB. With good accuracy.

If you jump to 4:00 on the video you will catch the twist rate, this rifle was noted for it's accuracy with round ball.

 

[dave951]

Rather than twist rate or in consideration with twist rate, look at the width of the lands to the width of the grooves and the depth of the grooves. You want the lands to be equal to or less than the groove width. You want groove depth to be 0.010" to 0.012" deep (square bottom) or 0.014" to 0.016" for radiused grooved barrels to properly hold the patch and contain the fouling between shots. Great performance can be obtained with twist rates from 1 in 48" to 1 in 60".

Good consideration of load development will result in excellent accuracy in jaeger style rifles with twists in the one turn in the barrel length (1 in 28).

Rifles built by Jake and Sam Hawken used the 1 in 48" twist rate and excellent accuracy has been recorded with their rifles. They used 0.010" or slightly deeper groove depth.

So, whether it is 1 in 48, 1 in 60, 1 in 66 or 1 in 70, pay close attention to groove depth and land width.

That's assuming shooting only PRB. Minies shoot best with shallower rifling. Again, it's what are you planning on doing that should drive the final decision. Know this, if you go for a compromise, you'll have just that.

 

[Bad Karma]

What is your barrel twist preference and why? Do you prefer a 1:48 twist barrel? Do you prefer a 1:66 twist barrel? Why do you prefer one over the other? Which twist rate is more widely preferred in the muzzle loading community?

1:48 is probably the most common. But as others have said, it depends on caliber and what you intend to shoot from the rifle. If you want an accurate round ball rifle and you’re recoil sensitive you might want a .45 with a 1:48 twist, maybe even quicker than that. Light loads and smaller bores generally require faster twists for higher revolutions per second. The opposite applies for heavier charges, and (higher velocities) larger bores. As an example, a friend shoots an unmentionable rifle, .45 caliber with a 1:22 rate of twist. He only shoots patched round ball and very light charges around 40 grains of 3f blackpowder. That rifle is very accurate within 50 yards which is exactly what the owner wants from it. It might be disappointing to increase his charge to 90 or 100 grains.

 

[Okie Hog]

i've had very good accuracy with rifles with twist rates low as 1/32 inches. One of my rifles has 1/38 inches twist rate. It's deadly accurate at 100 yards using PRB and 90 grains of powder.

http://whitemuzzleloading.com/round-balls-in-fast-twist-rifles/

 

[ASMman]

Hello Bent Sight,

I have read that 1:48 was an original twist rate, I'm not sure.
I know the Spanish Imports (CVA) were originally 1:66 on the .50 calibers and they shot quite well with a patched round ball. I had both a TC Hawken and a CVA Frontier Rifle,
both had 28" barrels. TC was 1:48, CVA was 1:66, I could out shoot the TC with the CVA every time with a .490 patched round ball over 80 gr. of FFF Goex. Later CVA's and Tradition's are rifled at 1:48, I don't know why.

I do believe for shooting patched round ball two things really determine optimum rifling,
Ball Diameter, and Speed of Projectile. As time has passed me by, I can't shoot like I used to. If I could, I would play with different charges as I think speed would have made that old TC shoot better. One of the guys which I shot with only used 60 gr. (unknown powder) at the range in his TC, and he could shoot.

Here are a few links to read,
https://americanlongrifles.org/forum/index.php?topic=25296.0
https://americanlongrifles.org/forum/index.php?topic=2040.0
http://www.namlhunt.com/mlconicals.html

AntiqueSledMan.

 

[Loyalist Dave]

What is your barrel twist preference and why? Do you prefer a 1:48 twist barrel? Do you prefer a 1:66 twist barrel? Why do you prefer one over the other? Which twist rate is more widely preferred in the muzzle loading community?

As long as it's not faster than 1:48 a load can be worked for a PRB. With good accuracy.

i've had very good accuracy with rifles with twist rates low as 1/32 inches. One of my rifles has 1/38 inches twist rate. It's deadly accurate at 100 yards using PRB and 90 grains of powder.

So it's a funny thing, twist rate with round ball.

The British found just after 1800 that for a combat rifle, at least 1/4 turn was needed to gain any advantage from rifling. They were looking to hit a 2'x6' target, anywhere on that target, at 300 yards with their new rifle, The Baker. Not what we'd want for hunting or targets, but it was a pure combat weapon. They settled on 1:120 twist rate, or perhaps a little faster...I've heard it was 1:110 to allow for the space taken up by the breech plug and powder charge.

We find that rifles in America that have survived, and rifling machines that have survived, seem to mostly be 1:48 twist rate.
We also know that in Germany, they had much faster twist rates, for round ball, even as fast as 1:28, and the Pedersoli jaeger repro, has an über-fast twist rate of 1:24, but it shoots round ball well. One of our members has had success with a faster than 1:48 twist rates, and is quoted above.

(Did you catch it? über-fast talking about German rifles? HA!...OK never mind...back to the topic)

Curiously, The British tested rifles captured in the AWI, and did not like the twist rate. We don't know what the rates were, but IF the surviving examples are a good indication, perhaps some if not most were 1:48. The British designers complained that the rifles had a "disagreeable recoil" with large powder loads intended to reach 300 yards. It's a big guess, but they were likely referring to torque as a result of the large powder loadings, since they settled on a much slower twist rate, and thus would've reduced the torque, ...i.e., the slap of the stock against the shooter's face when firing the rifle. (They also could've had stocks that didn't fit the tester well, which will often "hurt" the shooter when firing.) They didn't give us much detail as to what they meant by the term "disagreeable".

So what was the "magic" of the 1:48 twist barrel? It was decades before the invention of the Minie Ball, and the idea that it is a "compromise" twist to shoot both the conical and the round ball well, appears to be a 20th century thing.
Was it the fastest twist that the average person working a rifling machine could handle? It did take some muscle power.
Was it used on some very well made barrels, which gained a reputation, and thus it became the "popular" twist rate? How?
Did the riflesmith in the village take a hard look at a really accurate barrel or two from another builder, and measure the twist rate and said, "Ah Haaaa!" ? And so did the next one down the road, and so on and so on... I mean how many buyers back then ever checked their rifles to ensure they actually got that twist rate? How many ever asked ??
Why not 1:50...why not 1:46 ???
How come today we have choices in factory made barrels, in .45 caliber and larger caliber barrels, but IF it's under .45...so .40 and smaller, they are all 1:48, for the most part?

I have rifles that are 1:48, 1:56, and 1:60. From .40 to .54. They ALL shoot better from the bench than I can shoot them from just about any position that doesn't use a bench...except prone since I haven't tried them prone. It's fun to talk about as twist is curious, but I don't worry about it as long as I can hit what I aim at.....

LD

 

[nkbj]

Sounds as though with the Baker being a military arm they sensibly chose the slowest twist that would do the job at the level of force they wanted applied. One turn in nine or ten feet for a ball about 350 grains, yeah that's about right. Big ball slow twist, small ball fast twist. You know, wrapping your brain around the interplay between mass, spherical diameter and RPM ranks right up there with UFOs, sour dough starters and thirteen year olds.