Optimal Rifling Twist for a .54 Cal Rifle?

[Kestrel]

I'm thinking about a T/C rifle from their custom shop in .54 cal. What is the optimal rifling twist for using bullets in this caliber? I don't know if I will occasionally use PRBs, but maybe. I think I will primarily use bullets.

By the way, are sabot bullets available in this caliber?

Thanks.

 

[Voodoochile]

Sabots are available for a .54/.45 caliber combination.

PRB's mostly like a slow twist of around 1:66 or slower but the 1:48 twist seems to be a fair compromise for the PRB's & conicals, & sometimes works well with the sabots.

Now that is not to say that it'll be a tack driver with all 3 different types of bullets & you'll definitly need to taylor your loads for each for the best grouping but the 1:48 twist rifling tends to be a decent twist that'll make for good accuracy for all 3 types of bullets.

 

[arcticap]

I can't tell you the optimal rifling twist for all .54 caliber bullets since that would depend on the weight and overall length of the actual bullets being fired.
The faster the twist, then generally the longer and heavier the bullets that can be better stabilized during flight. After that it's the bullet velocity and RPM's (rotation) that stabilze the bullet once it leaves the barrel.
I think that most fast twist .54's have a 1 in 28" twist, but maybe someone makes it in 1 in .24" twist too.
Specific size sabots are available to shoot a variety of bullet calibers out of .54's including .429 -.430, .451 -.452, and .50:

http://www.mmpsabots.com/

Unfortunately, not every make of rifle will shoot bore size lead conicals the same or as well as sabots.
And shooting a heavy .50 or .52 caliber conical can have better or as good performance than a lighter .54 conical has. It's all relative to bullet length, weight and the range.
Some guns really do shoot both well, but sometimes it requires custom made and properly sized conicals to obtain the best accuracy. Some of the .50 caliber conicals weigh around 400 grains, so the recoil is felt.

http://bullshop.gunloads.com/

TC has made or makes .54 rifles with 1 in 28", 1 in 38", 1 in 48" and 1 in 66" inch too. They all have a niche for shooting certain projectiles.

For instance, Knight has a line of .52 caliber rifles that they claim has better performance and longer range than the .54's:

http://www.knightrifles.com/catalog.aspx?catid=de726h

Knight's short barreled Limited Edition .54 Brush Gun has a 1 in 28":

http://www.gmriflebarrel.com/

 

[Kestrel]

Thanks for the info. I forgot to mention, the default configuration on this one is 1:48 twist. I'm trying to determine if I should have them change that, but don't know.

Thanks again.

 

[arcticap]

I didn't realize that you were focusing on a traditional model.
The .54 TC Black Mountain Magnum has a 1 in 38" twist to better shoot conicals with.

T/C's Black Mountain Magnum was designed for hunters who desire the looks and handling of a traditional side lock, but want the state of the art performance of a modern styled in-line. The Black
Mountain Magnum .50 Caliber rifle has a 26" barrel with a 1 in 28" twist; designed for use with modern sabots or conical bullets (the .54 caliber rifle has a 1 in 38" twist). Its QLA® Muzzle System improves accuracy by providing exact bullet alignment from shot to shot, and it makes reloading a follow-up shot in the field "a snap". The composite stock is completely weatherproof, and the rugged steel adjustable sights (with fiber optic inserts) feature competition click adjustments and rugged durability for any hunting situation. The internal breech area of the Black Mountain Magnum has been designed specifically to accommodate the modern Pyrodex® Pellets as well as loose black powder or Pyrodex®, and coupled with musket cap ignition, it is as reliable and powerful as any muzzleloader in the market today.Caliber .50 or .54 cal.
Ignition Musket Cap for fast, positive ignition. A standard No.11 nipple is also included
OAL 41 3/4"
Barrel 26" Rifle - .50 Cal has a 1 in 28" twist, .54 Cal has 1 in 38" twist, both with QLA® Muzzle System.
Trigger Single with large trigger guard bow
Weight Appx. 7 lb
Stock Black composite stock or American Black Walnut
Sights Competition click adjustable steel rear sight and ramp style front sight are fitted with Tru-Glo Fiber Optics for precision shooting in low light conditions
Loading The Black Mountain Magnum can accept Magnum charges of up to 150 grains of Black Powder or Pyrodex® equivalent (or 3 Pyrodex® 50 caliber, 50 grain Pellets)
Extra Features Aluminum ramrod is standard on the Black Mountain Magnum rifles