An Advantage Of Slow Twist Barrels

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The old timers often used reduced charges when hunting small game.

Way back when I owned a .50 caliber muzzleloader with 1/72" twist rate. At one shooting session i watched as my mentor, "Uncle Joe", shot a three shot 50 yard group using patched round balls and 60, 70 and 80 grains of Du Pont powder. The bullet holes were touching. Yep, a slow twist barrel will put the balls in the same group with varied powder charges.

As the twist rate gets slower more powder is required to stabilize the balls. Among my junk is a .,50 caliber Navy Arms Hawken in good shape. Because of the fast twist it's useless to me. Sometime this year it will become a .54 caliber with slow twist barrel.
 
These days unless you get custom bp gun most if not all manufacturers provide 1:48 twist.
Lyman and Pedersoli are the few still producing slow twist rate barrels.
I have a Lyman .54 GPR kit fun with slow twist thatI purposely chose, my other is a Green Mountain.58 drop in TC Hawken.
 
The old timers often used reduced charges when hunting small game.

Way back when I owned a .50 caliber muzzleloader with 1/72" twist rate. At one shooting session i watched as my mentor, "Uncle Joe", shot a three shot 50 yard group using patched round balls and 60, 70 and 80 grains of Du Pont powder. The bullet holes were touching. Yep, a slow twist barrel will put the balls in the same group with varied powder charges.

As the twist rate gets slower more powder is required to stabilize the balls. Among my junk is a .,50 caliber Navy Arms Hawken in good shape. Because of the fast twist it's useless to me. Sometime this year it will become a .54 caliber with slow twist barrel.
Will a 1:48 twist rate still keep patched balls in the same group using varied powder charges? ( i.e., at around 50 yards)
 
Right you are Marty. I'm expecting the Sharon 1-72 I just bought to need a good load of powder to be accurate.

Although the seller told me that he used from 35gr to 140gr and it was accurate at all loads. That doesn't seem possible but we'll see.
 
Will a 1:48 twist rate still keep patched balls in the same group using varied powder charges? ( i.e., at around 50 yards)

IME: No.

BTW: There are two "compromises" with 1/48 twist, the twist rate and the shallow rifling. Patched round balls work better with deeper rifling.
 
Wow, thoroughly confused now. Thread started saying slow twist barrels like 1:72 best to shoot prb in same spot using different powder loads, by end of thread 1:48 also good? Isn't that a much "faster" twist?
 
Not sure anybody said a 1-48 is better than a slow twist with a PRB. Especially, if the rifling is shallow.

A 1-48 can shoot good but if you talked to a target shooter who used a PRB he'd be using a slow twist deep rifling barrel.
 
Most of the current production guns that have a 1:48" twist rate have shallow rifling as a compromise to shoot PRB or conicals. If you push a PRB too fast, it will trip over the rifling and your accuracy will go to pot. Think of a pitcher throwing a baseball. If he puts spin on the ball it curves to one side or the other depending on the spin direction. A knuckle ball thrown without spin requires more oomph to get over the plate and it usually drops down. Slow twist barrels with deep cut rifling a like the knuckle ball. They usually require more powder to get on target, but mutiple power levels can be achieved for different distances.
 
AMEN! And the rifling depth in the 1-48" bores is THE key factor that seems to escape some shooters. :thumbs up:

Good morning Hanshi. I own two muzzleloaders both with one in 48 twist, and just ordered another Percussion and it is 1 in 48, But only has a 24 inch barrel. I don't really know how to measure the depth of the rifling, but the first two seem to shoot fairly well with a PRB and up to 70 or 75 grains Of 2F. I've killed two deer and one antelope with 55 grains of 2f. I'm not a long-range shooter, so to me 60 yards is a long shot. I have my hunter safety kids shoot a 50 percussion using PRB's and 10 grains of powder, either 2f or 3f, at a paper target in front of a slanted steel backstop. At that distance, the balls are flattened to close to the size of a $.50 piece. It probably isn't cricket, but at 50 feet I would think that that would penetrate the side of a deer for a lung shot. I now have a dog from three different liters, as one is a TC, one is a Lyman, and this new one is going to be a Pedersoli. When the weather gets good, I've got lots of experimenting to do.
Squint
 
60 yds is my range too. I love to sneak in close. I use more powder than you but that's mostly for elk and bear. I'd use less for just deer. Not sure about 55gr like you're using but maybe 70-80gr.
 
Pretty sure most rifles that are 1:48 have .010 and deeper rifling except T/C.
T/C decided to rifle theirs at about .004 with a compromise 1:48 twist
They did this so the could shoot RB and Conical.
They did however make a few with 1:66 I believe just for RB, but just a limited run
and the barrels are marked as such.
The T/C's are finicky about patch and ball combo.
I am thinking about replacing mine with a GM 1:66
 
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True on the depth of rifling. Thompson Center uses shallow rifling with which I’ve used both prb and conical. My TC Hawken 54 loves TC Maxi-ball and Lyman Plains bullet (both with Ox yoke wad), My TC Hawken 50 will be shooting the TC Maxi-Hunter and my TC Renegade 50 loves the Hornady FPB and my cast patched rb. My Pedersoli Frontier 50 with 1:48 shoots awesome groups with prb.
I still always go back to prb with slow twist as they are just simply lethal ;)
 
Pretty sure most rifles that are 1:48 have .010 and deeper rifling except T/C.
T/C decided to rifle theirs at about .004 with a compromise 1:48 twist
They did this so the could shoot RB and Conical.
They did however make a few with 1:66 I believe just for RB, but just a limited run
and the barrels are marked as such.
The T/C's are finicky about patch and ball combo.
I am thinking about replacing mine with a GM 1:66


GM drop in should be 1-70 but hard to find now. Unless you're talking about buying just the barrel and adapting it. I talked to GM and asked them about the 1-70 twist. They told me they did a lot of testing and found the 1-70 worked the best for a PRB.
 
A friend of mine for 30+ years shoots a TC Hawken (1:48) patched round ball only. He has won many shooting events over the years with that rifle. Fast twist can shoot a round ball just fine, but the best load window, I think, is smaller than a slower twist. He found the right charge, patch, lube and ball size to make his deadly accurate. Anyone can do the same.

I have a new to me .45 with 1:48, and on the 4th sighting in and load work trip to the range I finally got it to shoot a very nice group at 50. Move the powder charge up 5 grains and the 1/2" group went to 3 inches. That much difference really surprised me. I also discovered it did not group unless wiped between shots. I've never had a rifle this touchy about loading before.
 
The TC shoots fine if you don't use a heavy hunting load. TC expected you to use a conical for that. They made the Maxiball for their guns.

The original Hawken had a 1-48 twist but it was deep grooves. I've always preferred the slower twist. I had a Renegade that I put a GM drop in barrel with a 1-70 twist. Man, that was a good shooter.
 
I have a 1:70, 1:66 and 1:60 ROT that are all most accurate with 80 grains of powder. The 1:60 likes a different powder than the other two, but still uses 80 grains nonetheless. I do not consider that a "stout" load or "a lot" of powder. I've tried 100 grains and even 120 grains and accuracy went down in all of them.
 
I will be going out Tuesday morning to shoot.
Will be taking the T/C Hawken 1:48 shallow groove and my new to me CVA Mountain
with deeper grooves and I believe 1:66 twist.
Will try the Hawken with lighter loads and the Mountain with varied loads.
We will see what happens.
 

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