58 cal

[hortonstn]

I acquired a 58 cal barrel 42 inches long 1-72 twist the barrel has no mfg name on it
8 groves thin rifling
Anyone have any experience with this type of barrel is a 58 accurate for bench use?
Thanks paul

[Hungry Horse]

The barrel makers that favor 1in 72” twists are not as prevalent as those that favor using  a faster twist. It being unsigned makes me think of Montana barrels, and all the other companies that followed, and used their machinery. They  usually are about twelve thousandths rifling. They do shoot well, but .58 cal. and a 1 in 72” twist is going to take a lot of powder to stabilize the ball. If you really like a swift kick in th puss it’ll probably work out fine. But, if you are recoil sensitive, more than three or four shots off a bench will probably make you want to call it a day.
 Offhand shooting doesn’t beat you up so much, but a 42” barrel is going to be heavy even in the thinnest configuration in a .58 caliber.

  Hungry Horse

[smylee grouch]

I think most heavy bench guns are 58 cal. or larger but they most likely have a larger than average outside diameter thus have more weight. 150 gr. and up for powder charges.

[OldMtnMan]

Shoulder recoil pad, soft cheek pad, and don't flinch.

[walks with gun]

   Might work out great for a wide butt transitional type gun.  What were you thinking of using it for.  It could take a lot of load experimentation but will probably be worth it.  You never know it could be a light load tack driver.

[RichG]

I have a green Mtn. 58 with 1-72 twist. shoots fabulous with 75 gr 3f goex .020 patch wet lube and a .575 ball. gun weighs 10 1/4lbs , hardly recoils at all. Also shoots great with 150gr. 2f .025 grease patch and .526 ball. (not a bench/target load). adjust your components and you can generally get a barrel to do what you want.

[OldMtnMan]

I thought GM barrels were 1-70 twist?

[Tim Ault]

The barrel makers that favor 1in 72” twists are not as prevalent as those that favor using  a faster twist. It being unsigned makes me think of Montana barrels, and all the other companies that followed, and used their machinery. They  usually are about twelve thousandths rifling. They do shoot well, but .58 cal. and a 1 in 72” twist is going to take a lot of powder to stabilize the ball. If you really like a swift kick in th puss it’ll probably work out fine. But, if you are recoil sensitive, more than three or four shots off a bench will probably make you want to call it a day.
 Offhand shooting doesn’t beat you up so much, but a 42” barrel is going to be heavy even in the thinnest configuration in a .58 caliber.

  Hungry Horse

   
    Your statement about the round ball stabilizing has me thinking , unlike a bullet  how can a round sphere/ ball be stable or unstable ?  Yes it will have rotation imparted from the rifling but how is it going to yaw or become unstable with more or less speed from more or less a powder charge ? I understand how bullets act with different twist rate and speeds but how can a round ball become unstable ?

[rich pierce]

Think baseball.  The knuckle ball is erratic and unpredictable because it has no spin.

[Tim Ault]

Think baseball.  The knuckle ball is erratic and unpredictable because it has no spin.

    True but a rb does have spin/ rotation and that is dictated by the twist in the barrel regardless of the speed be it 900 fps or 2000 fps  still the same spin rate regardless speed

[smylee grouch]

I have been told that the rotational speed is increased as you increase your velocity and also decreases as you lose your velocity. If thats true more scientific minds might have to explain how as I can't.     

[Standing Bear]

Rate of Spin of a projectile increases with muzzle velocity.

Though the rate of spin does decrease over its time of flight, but it decreases very little as there is little resistance to the rotational motion.
TC

[OldMtnMan]

I would think a ball has a sweet spot for spin speed. Too fast a twist and it's not accurate. No spin and it's not accurate. Somewhere in the middle is what we want.

[Bill Raby]

I have been told that the rotational speed is increased as you increase your velocity and also decreases as you lose your velocity. If thats true more scientific minds might have to explain how as I can't.     

72" twist means the ball rotates once every 6 feet. At 900 fps it will rotate 150 times in one second. Thats 9,000 rpm. At 2000 feet per second it will rotate 333 times ion one second. Thats 20,000 rpm. Ball rotates once every 6 feet no matter what the velocity is. When you double the velocity the ball is just covering that 6 feet and one rotation in half the time.

[Bob Roller]

Shoulder recoil pad, soft cheek pad, and don't flinch.

The first real muzzle loader I made was a 33",one inch across the flats 58 caliber.
It was a match winner.It was also the first octagon barrel Bill Large made when he
got his big shop finished in 1958.I made it into a walnut half stock rifle with silver
butt plate and trigger guard and single set trigger.IF I were to make another it
would be stocked like an English long range rifle with shotgun butt.

Bob Roller

[OldMtnMan]

Shoulder recoil pad, soft cheek pad, and don't flinch.

The first real muzzle loader I made was a 33",one inch across the flats 58 caliber.
It was a match winner.It was also the first octagon barrel Bill Large made when he
got his big shop finished in 1958.I made it into a walnut half stock rifle with silver
butt plate and trigger guard and single set trigger.IF I were to make another it
would be stocked like an English long range rifle with shotgun butt.

Bob Roller

When I was young I thought recoil was fun. I worked a gold claim in Alaska with a bud. I had a 458mag that I shot 500gr bullets out of. The first time I shot it it knocked my hat off. I just laughed and kept shooting. It was my grizz charge stopper. They were everywhere around the claim.

 Now, i'm very sensitive to recoil. I had skin cancer removed from my cheek and it left it very sensitive. Plus, I don't have the meat on my shoulder I had when younger. Some guys get fat when they get older. I got skinnier. It's probably why I hate to do any bench shooting. It hurts more than offhand.

[OldMtnMan]

I have been told that the rotational speed is increased as you increase your velocity and also decreases as you lose your velocity. If thats true more scientific minds might have to explain how as I can't.     

72" twist means the ball rotates once every 6 feet. At 900 fps it will rotate 150 times in one second. Thats 9,000 rpm. At 2000 feet per second it will rotate 333 times ion one second. Thats 20,000 rpm. Ball rotates once every 6 feet no matter what the velocity is. When you double the velocity the ball is just covering that 6 feet and one rotation in half the time.

  I've been thinking about this since I read it yesterday. I agree with what you said as long as the ball is going down the bore. What happens after it leaves the bore. The rifling is holding the ball to that twist, but once free of the bore why can't the ball pick up rpm?

 Think of a pitcher throwing a ball. It has zero rpm while the ball is in his hand, but starts to turn rpm when released and continues to gain rpm until air resistance slows it down. A bowler is the same way. RPm accelerates as it rolls down the alley.

 So, why wouldn't the ball/bullet do the same thing? We shoot different loads of powder trying to find the most accurate load. What is changing when we got from 80gr to 90gr. What makes that 90gr load more accurate? Is it a different spin rpm on the ball? Has this ever been measured? A chrono measures speed, but do we have a way to measure ball rpm at different distances?

 We know a smooth bore is only accurate at closer ranges. I never see a smooth bore target shown for 100yds. No ball rpm is not accurate at longer distance. A modern muzzleloader have a 1-28 twist. (mostly) They can shoot a round ball, but have to use a light load. Too much ball rpm to accurate at long distance.

 So, it seems to me that ball rpm has something to do with accuracy. By using more powder it will shoot flatter, but shouldn't effect windage if we leave the wind out of it. By using more powder is it the velocity that only matters for accuracy, or is ball rpm part of it too? When we develop a load we're using the same gun and bore twist. I think ball rpm matters after it leaves the bore.

 I layed in bed this morning thinking about this. I had to write it down and see what others thought. Of course, we don't need to think about this when developing a load, but it is something to think about.

[axelp]

Am I right in thinking the actual ball spin will not match the twist in the barrel exactly? I am thinking that some slippage occurs probably at the beginning. So a 1:72 twist will not equate exactly to a ball spinning 1:72. Closer at the muzzle, not as much at the breech. Of course that also depends on how tight the patch and ball is in the bore. A looser combination might slip more, a tighter combo less?

K

[smylee grouch]

Interesting  food for thought there old mt. man. I don't know of any tests or methods to test the rotational spin. Sounds like a good question for the science guy. May be some one else here can point out some tests or data on the subject. I'm sure there are more than one opinion on this.     

[Daryl]

The only way to find out if it will shoot, is to shoot it.

Most barrels made with what we assume are round ball twists, shoot very well indeed.

You simply must try it with a variety of loads and combinations to find one that suits.

I have had .58's with 48" twist, 56" twist, 66" twist and two at 72" twist. 

The .56" twist was a Pedersoli Kodiak which shot best (regulated) with 110gr. 2F, a .562" ball and standard 10 ounce .0225" denim or .0215" ticking patch. By regulated, means it shot into two

groups, the centres of which were bore axis apart at 50 yards.  That means it shot parallel. With 100gr. of 2F powder, it shot both barrels into a 1" group for 6 shots, 3 from each barrel at 50

yards.

My 66" (GRRW) shot best with 140gr. 2F GOEX or 160gr. C&F, but that was back in 1978 or so, with poorer quality powder than today.  I used a .575" dead soft led ball and .022" denim, twice

washed with spit as well as Neetsfoot oil for lube.

One of the 72" twist rifles (Zouave) shot best with 120gr. + .575" soft ball while the other (Numrich) wanted 140gr. 2F to do it's best, same ball and patch, same twist, but 20gr. difference in

 powder. All this shooting was at 100 yards, off bags and 2" was the goal, achieved by all, but the 48" twist model 1861 Musketoon of Army San Polo make. It's best was 5 shots into 3", however,

it did that with 82gr. (3 drams) 2F, a .575" ball

(.001" larger than the muzzle's bore) along with a .020" denim patch - no cutting, good super tight load in the .003" rifling at the muzzle. This barrel had progressive depth rifling and may have

been a PH barrel. I had no difficulty hitting the 200 meter steel plate (16" square) at our Black Water range.

So - you see, you must find out for yourself what your barrel wants for it to produce it's best accuracy, if that is the goal.

Mediocre accuracy can be had with a much wider variety of loads and combinations.  The resulting accuracy can be whatever you want.  Note, I generally found the slower twists shot better with

more powder.

[Daryl]

Am I right in thinking the actual ball spin will not match the twist in the barrel exactly? I am thinking that some slippage occurs probably at the beginning. So a 1:72 twist will not equate exactly to a ball spinning 1:72. Closer at the muzzle, not as much at the breech. Of course that also depends on how tight the patch and ball is in the bore. A looser combination might slip more, a tighter combo less?

K

My own thoughts on this, are that the ball with a tight combination (I know of no other way of loading) will not slip at all. However, even if it did but then grabbed hold (as some modern cast

bullets do) and was introduced at the muzzle from a rifled tube, would then start it's travel with exactly what ever the twist of the barrel actually was. Whether or not it slips at the start is

immaterial. How it is delivered from the muzzle is the important point.

We know that slippage does happen with 'some' cast bullets in modern handguns.  Does it happen with patched balls - likely with many of the loads used today by those who do not wish to hit,

or perhaps do not care whether they hit what they are aiming at or not.

To slip or not to slip - WHAT is the question? - whether 'tis nobler to hit or miss, is THAT question?

[hortonstn]

To bring you up to date this rifle really impressed me
Of the bench 60 yards 75ff .570 ball .20 teflon ticking two groups small than 2 inches
Open sights I tried 80ff and 100ff all that did was hurt my shoulder
Don't under estimate the.58
Looking forward to light bench this will work
Paul

[Daryl]

Well, you are on your way, Paul. I suggest you obtain a P.A.S.T. strap-on shoulder pad and test this rifle with the powder

charges you are likely to need, to obtain better accuracy.

 In the larger calibres, I have found 2F to give better accuracy - which might be attributed

to it's lower pressures generated at ANY velocity.   For your barrel, there will be a velocity that delivers the BEST accuracy.  2F will deliver that

velocity at a lower pressure than 3F will.  The lower pressure is kinder to the ball and patch combination.

2" or even 1 1/2" is not especially good for a hunting rifle, let alone for a match-to-be rifle.

At 5 shots into 1", you are now approaching what you should be shooting - that being about 1/2" or hopefully, a bit better than that.

Back in the 70's, the cross-stick shooters at Friendship were shooting 3/8" groups at 50yards.  THAT and better, should be the goal.

1" and better should be the goal at 100yards.

[Mike Brooks]

I'd be pickled tink if I could shoot 2" at 50 yards with open iron sights these days.

[OldMtnMan]

Yes, a 2" group will kill every big game critter you shoot at. As long as you can find the middle of the kill zone.