Lyman

[William A Harland]

I have one of the first model Great Plains 54 cal black powder muzzleloader can any one tell me what the twist is? have they change them form the older model It has never been fired, new.

 

[hanshi]

As far as I know - and I'm probably wrong - the GPR has a slow, round ball twist maybe 1-60" or possibly 1-66".

 

[BullRunBear]

Got my GPR 50 caliber flinter about 15 years ago. The twist is either 1:60 or 1:66.

Jeff

 

[firestick]

I believe they were advertised as 1-60

 

[longcruise]

I acquired mine in 1980 or 81 and it had a 1:48. I eventually switched it to a GM barrel.

 

[rodwha]

I acquired mine in 1980 or 81 and it had a 1:48. I eventually switched it to a GM barrel.

Sounds like you have a Trade Rifle or Deerstalker with a 1:48” twist. The Great Plains Hunter or Rifle has much different twists.

 

[longcruise]

Sounds like you have a Trade Rifle or Deerstalker with a 1:48” twist. The Great Plains Hunter or Rifle has much different twists.

Nope, it's a GPR.

 

[Cowboy]

I have to ask my friend.

Is it a Lyman Great Plains Rifle or Is it a Lyman Plains Rifle??

Another question would be, does this rifle have an over sized patch box that covers the majority of the butt area of the stock? ( would be large brass patch box )

This information would be vital in determining the twist rate that your seeking my friend.

A pic would be better yet!

Respectfully, Cowboy

 

[rusty]

I think the GPR is 1 in 66

 

[Cowboy]

I think the GPR is 1 in 66

The GPR is 1:60 my friend.

Am trying to determine if the OP has a GPR or a PR ? Definitely two different rifles.Different twist rates as well?

Respectfully, Cowboy

 

[rodwha]

Nope, it's a GPR.

Interesting. My understanding is they’ve only come in the slow 1:60 and fast 1:32 twists. What year is it?

 

[mushka]

Measure it yourself. Put a tight patch on the cleaning rod, then push it til it seats. Put a mark on the top of the rod that is easy to see, then carefully pull the rod out(making sure the rod is turning with the rifling)and when the mark is again on the top mark the rod at the front of the barrel. Measure and you have the length of your rifling twist.

 

[Grenadier1758]

Or when the mark is half way around, since most of us don't have 48" barrels.

Multiply by two if you measure at the half turn.

 

[longcruise]

Interesting. My understanding is they’ve only come in the slow 1:60 and fast 1:32 twists. What year is it?

This was a kit and was on sale at a local sporting goods store. Someone had bought it and returned it. Probably out of frustration. That was about '79 or '80. I still have the barrel and I'll check the twist of it.

 

[Chrisp]

I have a Lyman GPR made in 1990, the manual that came with the rifle stated it was 1:48 twist, and the manual is definitely for the GPR, and my rifle is definitely a GPR,I bought the rifle new from DGW in 1990. I have not actually measured it though, but it is accurate with conical as well as RB. I believe I have seen older posts on this subject and the older GPR had the 1:48 twist, at least around the 1990 date.

 

[William A Harland]

Thanks call Lyman to day told me 1-60 twist Thanks for all the answers. Can i shot a sabot bullet out of it?

 

[William A Harland]

As far as I know - and I'm probably wrong - the GPR has a slow, round ball twist maybe 1-60" or possibly 1-66".

Thanks Lyman told me a 1-60

 

[William A Harland]

I have a Lyman GPR made in 1990, the manual that came with the rifle stated it was 1:48 twist, and the manual is definitely for the GPR, and my rifle is definitely a GPR,I bought the rifle new from DGW in 1990. I have not actually measured it though, but it is accurate with conical as well as RB. I believe I have seen older posts on this subject and the older GPR had the 1:48 twist, at least around the 1990 date.

Layman tole me a 1-60 twist Thank You for your reply.

 

[William A Harland]

Interesting. My understanding is they’ve only come in the slow 1:60 and fast 1:32 twists. What year is it?

Lyman could not tell me the yr. they said it was a 1-60 twist. Thank You for your reply.

 

[Chrisp]

Layman tole me a 1-60 twist Thank You for your reply.

Well, I’m going to measure mine, should have done it a long time ago. Thanks for info from Lyman.