Twist rate in .50 White Mt Carbine?

[Hopalong7]

I've got an old (15-20 yr) T/C .50 White Mt Carbine w/ 21" barrel.  Used it a lot for tree stand close range shooting w/ 350 Maxi Hunter bullet and 100 gr RS. Kicked like a mule but hammered the heck out of many deer too!!! Never shot great but was OK for intended purpose. Always assumed the twist rate was 1:38.  Retired it 5-6 years ago due to 209x50 Encore.  Got it out of the safe recently to play with and decided to check the twist...SURPRISE...appears to be 1:24...didn't know T/C had anything w/ that fast of a twist back then. Couldn't find my old T/C catalogs but old Fox Ridge Catalog listed .50 barrels w/ either 1:38 or 1:48.  Anybody out there know the deal here or have similar rifle.   Thanks and GOOD SHOOTIN, Walt

[Hopalong7]

Thanks John,  that explains a lot.  Can't believe I had it that long and never checked.  GOOD SHOOTIN', Walt

[Kurt]

I gots one of them too. It's about 6years old and is a 50 cal. 38 twist. Johns right they did make a fast twist. I thought it was 1in 20. As I understand from talking to the TC techs, they switched cause the fast twist didn't like anything cept the short pistol bullets in sabots. Me thinks it was they were ahready well invested in tooling to do 38 twisters. Mine loves the 250gr 45 XTP in the TC HP sabot or the Nozler sabot. I think those sabots are from the same mfgr. THey're hard sabots. It shoots 490 RB super at lower 50 or 60gr loads w/ a tight patch. I shot numerous 3 inch, 100yard RB groups with it and a couple a little tighter than that with 45/50 sabots. Conicals are another story (i have many molds some customized) and I gots to use BP to even start to group with them. BP is best but sooty as all get out. Pyrodex is well,,,,,Pyrodex.

[savageT]

I've got an old (15-20 yr) T/C .50 White Mt Carbine w/ 21" barrel.  Used it a lot for tree stand close range shooting w/ 350 Maxi Hunter bullet and 100 gr RS. Kicked like a mule but hammered the heck out of many deer too!!! Never shot great but was OK for intended purpose. Always assumed the twist rate was 1:38.  Retired it 5-6 years ago due to 209x50 Encore.  Got it out of the safe recently to play with and decided to check the twist...SURPRISE...appears to be 1:24...didn't know T/C had anything w/ that fast of a twist back then. Couldn't find my old T/C catalogs but old Fox Ridge Catalog listed .50 barrels w/ either 1:38 or 1:48.  Anybody out there know the deal here or have similar rifle.   Thanks and GOOD SHOOTIN, Walt

From Thompson Center Service:
 
The T/C .50 cal White Mtn Carbine started with the 1-48" twist in 1989.
 
From 1990 to 1993 it has the 1-20" twist. In 1994 & 1995 it went to th e1-38" twist.
 
Very Truly Yours,
Tim Pancurak
PO Box 5002
Rochester, NH 03866-5002

savageT