1:48 Twist... The best compromise?

[CoHiCntry]

Up until now I've been shooting large lead conicals in my sidelock but would like to venture into shooting some PRB.  I've heard some say you need to pick one or the other, either slow twist for PRB or fast twist for conicals.  Much debate, I know...  Does everyone think the 1:48 is the best compromise to be able to shoot both conicals & PRB?

I've always been hesitant to start using PRB because I'm primarily a western big game hunter and am concerned about the effectiveness of the PRB compared to a conical.

What's everyone think about this?

 

[exMember]

Yes the 1:48 will do just about everything including round balls with extreme 100 yard accuracy to a light weight sabot. I've shot the 440gr lee bullets and they are an extremely round in this twist despite the bullet weight. The newest one I found is the 395gr lyman plains bullet which I really liked in my traditions. My shoulder hated it, but for hunting, a shot or two will not bother me lol.

You should have zero concern with a round ball for hunting. I've taken everything from rabbits, deer,elk with them. This year if I am able to go, I will be using my standard 70gr 3fg goex charge with a 490 round ball on my bear.

You have a bullet thats just under 1/2" diameter. Its going to penetrate.

The modern ballistic crap out there is for tiny bullets made of jacketed copper that needs a minimum about of energy in order to properly expand and transfer its energy.

 

[burlesontom]

It hard to add more than what FrontierGander said but remember the RB was the bullet of choice for many years. They early pioneers and settlers cleared out the elk and bison in the eastern forest with round ball rifles. Lewis and Clark used RB 54 caliber rifles on the corp of discovery trip. They did get chased by a couple of Grizzlies but in the end killed the bears. Grizzly bears take a lot of killing apparently.

Most of my guns are 1/48 twist. I have two rifles with 1/60 and 1/66 twist. I can't tell any real difference in accuracy between them. The 1/60 is my Lyman GP rifle. It shoots Lee 320gr and Lee improved Minnie very well also. Just goes to show that you just need to shoot a gun to see what it will do. But you will not go wrong with a 1/48 twist.

 

[strong eagle]

with a 50 cal 1/60 twist the gun wont be fussy about powder charge. 70 to over 100 grains it will work very well with a patched ball. use a .495 ball and not a .490 ball for best accuracy. a 1/48 twist works best a 70 grains. a 1/72 twist in a 50 cal has to be pushed hard and you need to start with at least 100 grains. i know you asked about the 1/48 twist but some day you may want something else. a 1/56 twist to a 1/60 twist is perfect for a 50 cal round ball rifle. a 50 cal round ball with 70 grains can go though a deer. the hole is the same as a conical. they pancake and make a big wound channel. the deer will not know the difference between a round ball or a conical. 45 is different. a 45 round ball doesnt do what a 45 conical can. again use a .495 round ball with a pure cotton denim patch cut off at the muzzle with 70 grains by volume of powder and you will have very good accuracy and place your shot where it counts and you will drop your game.  one year i hit a nice buck antelope at 100 yards with just this load in the shoulder. the ball split in two and the wound channel would have dropped anything. both front legs were broken and it was over for that buck antelope.

 

[Fyrstyk]

It is not the twist rate so much but the depth of the rifling.  Deep grooved rifling works best with a PRB, and shallow grooves work best with conicals.  The 1:48 twist used by the Hawken brothers in the 1800's had deep grooves for the round balls that were primarily used.  T/C used 1:48 twist also, but their rifles had shallow grooves so that conicals could also be shot.  With shallow grooved rifling, you can't push a PRB to fast or the ball will skip over the rifling and accuracy will go down the tubes.  Keep the velocity down to sane levels and it will shoot PRB's fine.  You have to remember, that only a small portion of a ball actually touches the rifling, where as the longer conicals have more bearing surface to engage the rifling.

 

[Sparkitoff1]

I am respectfully not in total agreement with the above posts. Having had 5 previous 1:48 rifles and currently using one 1:48 (all 50 cal) my experience has been different. Starting current and working back, this rifle will not shoot PRB with any decent accuracy past 35 yards. I've used the Dutch Schultz system, tried different ball sizes, patches and lube. Literally hundreds of combos. One combo looks great on the 25 yard target and is reasonable for about another 10 yards. After that, forget it. There may be a magical combo out there somewhere but I spent so many weeks and dollars trying to find it that I could have bought another rifle easily. I tried conicals and found one particular brand and weight that this rifle puts into small groups at 100 yards. Going back to the next most recent, it would shoot one combo with PRB very accurately making nearly one-hole groups at 50 yards and a respectable group at 100 yards. However this one combo had a muzzle velocity of around 1425 fps with a 177 gr ball and subsequently quite a trajectory curve. I wanted more velocity and a flatter shooting rifle than the performance it was accurate with. Next rifle back, it shot nicely with .495 balls and a .018 patch. While the rifle did its job without too much fuss, I was unable to get the .495 balls in the stores that carried ML supplies. Sure, I could order a pile of them or make them myself but at the time I could neither stockpile nor create. Due to this inconvenience I sent that rifle to a new home. The last two I will summarize in general terms because it was a long time ago. Both shot PRB very well.  One I have no idea what size balls or patches, as I shot what came with the rifle. I did not know much about BP them and I just loaded 100 grains of Pyrodex because that's what I had heard at the time. The other rifle I remember shooting every day for a month before deer season and it still wasn't ready on time. Eventually I figured out it did great if you shot about 3 shots without cleaning and started a group of 3-shots on the 4th shot. Shot 4, 5 and 6 would make a small group at 75 yards (that was the range distance at that time). I did not want to leave the gun dirty for days for fear of rust and I did not want to have to shoot 3 shots into nowhere before starting a hunt. 

In summary, of my 5 rifles with 1:48, only one did what I wanted it to do with PRB loads. Some of the others were accurate with PRB loads but the nuisances to get there were not worth it to me. 

On a similar note, I currently have a 1:60 .50 caliber that won't shoot PRB.  It was a gift and I like the looks and feel of the rifle so I invested a whole summer of shooting and trying PRB combos. After hundreds of dollars and probably over 100 hours I gave up. On a whim I tried a projectile called a Hornady PA Conical. 1.5" groups at 50 yards on the first attempt. I have not desire to keep messing with PRB for this rifle in spite of the 1:60 twist. The PA Conicals were $9.99 for 50 and don't need a patch or lube to group great. Each rifle is unique and a thing unto itself!

Best of luck!

 

[exMember]

I have 4 1:48 twist rifles on my wall and all will do well under 2" at 100 yards.

If you have poor grouping at 35 yards, that tells me its a barrel issue IMO.

My favorite hunting rifle stacks them at 100 yards with as much as 90gr.

 

[strong eagle]

man some people dont do research. DEEP GROOVES come on , get real. hawken rifles was shallow groves. not deep grooves. twist and ball size and good patch material is every thing along with the right powder charge. never tamp when ball is on powder. some people cant resist going off with nothing to back it up. when you can get small groups at 20o yards and beyond lets hear from you. the head of our mountain man group says he is tired of loud guys that say volkswagon size groups at 100 yards are good. if your not getting 50 cent size groups at 100 yards you are a hunter, not a target shooter. sorry guys too much crap from guys that have good typing fingers and no knowledge. i dont even shoot muzzleloader much any more, mostly cowboy. but when i did, i drove tacks. sorry im too old to be polite to people who know 0 and take over a honest question. cast boolits is full of that ****, go their if you want to blow hard. keep it real on this good site.

 

[Rifleman1776]

Sparkitoff, even with ml'ing being a very frustrating avocation, you sure seem to have a whole lot more problems than many others in this game. I can't respond to everything you said, that would take a week or more of typing. I'll just say, there are probably more 1:48" twist ml rifles out there than any other. Maybe more than all others combined. Look in museums, the 1:48" is the dominant twist in originals by 99 to 1 (my guesstimate). Rifling depth is not a factor other than affecting choice of ball size and patching. That said, the 1:56" is a very good second choice. In fact I have a rifle under construction now with a .50 cal. barrel in 1:56" twist.

 

[Sparkitoff1]

I agree that 1:48" is very popular and will work well with PRB. I have no idea what the depth of rifling is in any of the rifles I mentioned, nor the # of grooves.  I readily admit that with 2 of them I never tried anything but 100 grain of powder because at the time I did not know better. If you read carefully, 3 out of the 5 rifles I have used did group well with PRB's!  2 of them were just picky - an inconvenience to me but nothing against the rifles.  One wanted components I could not readily get at the time and the other was best at a velocity and trajectory that was less than I wanted. Only my current rifle in .50/1:48 I cannot get to group PRB's no matter what I've done, yet it shoots a certain conical just fine. That one I will name - A Traditions Deer Hunter (24" barrel). Just for contrast, I mentioned that my 1:66 CVA won't shoot a PRB.  It has a large bore diameter and has some pitting.  It does shoot a PA Conical perfectly. Not mentioned because it is outside the scope of the original question are my 3- .54 calibers, all of which shoot PRB just fine (1:70, 1:48 and 1:24). So, I don't think I have more problems than most. I just don't think 1:48" automatically make a rifle a better candidate than one with a different twist for PRB (as the original question asked).  My experience has been that it varies widely from rifle to rifle. My intent is not to discourage or dissuade CoHiCntry, but to give him some real information so if he experiences something similar initially, he can pursue a variety of options.

 

[burlesontom]

Boy howdy this discussion has heated up a little. This fellow here seems to get decent accuracy with his 1/48 twist rifle and PRB. There is something familiar about him though. :blah:

https://www.youtube.com/watch?v=ymF0DsCdKUI

 

[burlesontom]

I looked up some of the listed rifling groove depths in my new Dixie catalog.

Most Pedersoli guns have between .005-.007 deep grooves. The Mountain Hawken has a 1/65 twist with .011 grooves. They didn't list anything for their smooth bores.

The Great Plains rifle is shown to have .010 grooves in both 50 & 54 caliber. The Lyman Trade Rifle has a 1/48 twist with .010 grooves and the Deerstalker has a 1/48 twist with .008 grooves.

The Traditions guns are listed as having .009 for the Kentucky rifle, .007 for the Frontier rifle and Hawken Woodsman rifle.

So what does this tell us? I don't know. Except maybe that you just need to learn your rifle and what it likes. I have shot all of the above rifles and really couldn't tell any difference between them because of rifling depth or twist.

The biggest problem I had when I started shooting BP rifles was blown patches. Once I figured out that that was what the problem was and I used better patching material all my accuracy problems went away. So I don't get too wrapped up in twist and groove depth.

 

[exMember]

It makes sense that the faster twist rifles have shallower grooves. A barrel with .010" rifling would be pure hell or basically impossible to seal up with a conical bullet. Accuracy would be poor as well.

I've seen some barrels with .016" rifling and thats some really crazy depth IMO.

 

[burlesontom]

Thats probably why the T/C rifles worked so well with the Maxi Balls designed for them. They probably had .005 deep rifling. But the few I have owned all shot PRB pretty good. And I am not talking about target loads either. Just a couple of weeks ago me and a couple of friends were shooting BP rifles and one of those rifles was a T/C Hawken I built from a kit and sold to him. I knew it was an accurate rifle because I had shot it before.

We used PRB loads and he was tickled to death with the accuracy he was getting. He is not a BP shooter and I had to show him how to load and shoot the rifle. But he is a good shot and was pinwheeling the target with 70-90 grain loads at 70 yards.

I figured the deeper rifling was why you were using felt wads when you shoot the Lee 250gr conical in your guns to stop the blow by. I don't understand the need for .016 rifling either.

 

[burlesontom]

Well after talking about the various rifling depths I went and got my feeler gauge and dial calipers. .006 is not very much. Neither is .010. Heck even .016 didn't look all the big either. Now I am surprised these guns shoot well at all.