twist rate for a 58?

[Jac Spring]

I'm having my 54 CVA mountain rifle rebored to 58 caliber. I would like it to shoot patched balls accurately. What twist rate would be best for this caliber? I know slow - like 1:66 is good for the 54 but what about the 58?

TIA

 

[J.D.]

Many barrel makers use a 1-72" twist for a 58 cal barrel.

Some custom makers will use an even slower twist.

I'm no expert, but it doesn't take very much spin to stablize a round ball, so slower twists should work well.

J.D.

 

[Jac Spring]

Thanks. I did do a search and come up with a variety of opinions on this.

I was thinking 1:70 - I guess 1:66 to 1:72 isn't a huge difference though.

Probably worrying about nothing with this.

Mr. Taylor will most likely have some advice on this and I'll likely just go with that.

 

[MikeChapin]

The original .58 CVA Big Bore Mountain Rifles had a 1:66 twist. A friend of mine still has his from back in the early eighties and it still shoots great. My GM .58 has a 1:70 twist and it will cloverleaf at 50 yards. Anything from a 1:66 to a 1:72 should do fine.

 

[bub524]

I shoot alot of 58s. All CW muskets and they are 1-66 to 1-72. Most will shoot a one hole group, a big ragged hole mind you, at 50yds. withe various types of minies. None of them will shoot a PRB well. They do have shallower rifling however. That said I have one 58 Enfield with a 1-48 that shoots PRB rather well. I'm sure this just muddies the water more.

 

[Jac Spring]

Well, from everything that I've read and your input, I feel very comfortable with the 1:70 if that works for John. If his equipment is set for 1:66 or 1:72, I'll be very happy with it.

He knows that I want to shoot prb's too, so I'm sure he'll use a strong rifling.

Thanks for the feedback! :hatsoff:

 

[paulvallandigham]

With a slow rate of twist, PRB have to be driven at higher velocities to stabilize and be accurate. Most .58 shooters are used to using 60-80 grains of FFg powder. With a round ball, you need to switch to FFFg and increase that load to 80-100 grains. Then you get better accuracy with the PRB. :thumbsup:

 

[Jac Spring]

Thanks Paul!

I think I can do that :grin:

 

[paulvallandigham]

Oh, with those weights of FFFg powder, you may find those thin patches burning up, or having gas cuts in them. If so, use an Overpowder card, or a filler, on top of the powder to seal the gases, and save the patching. I would not worry about shooting a round ball in shallow rifling. I had a gun that had rifling that was barely scratched into the bore, and it shot fine, with about 55 gains of FFFg powder( .45 caliber, 25 inch barrel). I know there was another load about 30 grains that would recoil less, and provide good target accuracy, but I never spent the time and effort to find it.

 

[Jac Spring]

dang! I knew there was something I was forgetting - ordered some balls and patches... forgot the wads :shake: