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Lymans great planes rifle barrel, want more twist.

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Thank you sir!

So there is a drop in barrel with a faster twist available?
He is correct. Lyman kept the GPR name when they switched to Pedersoli but so far as I know the Pedersoli ones all have Signature Series added to the stampings on the barrels. I can post pics of the examples I have but won't be able to tonight.

As far as a readily available drop in I haven't been able to find one short of a custom order from a barrel maker. I peruse Gun Broker and EBAY a couple times a week and there just isn't much stuff that pops up for them. As I stated above there are more that come up in the classifieds here than any other sites I frequent.

There is one thing to add. Invetsarms is still selling these rifles under their own model so a replacement barrel for one of those might be able to be had from them. The Pedersoli ones have been pulled from their site, the only way to find it is to search a part number from owners manual and I don't think they offer anything for them, it all had to be obtained from Lyman and they are now out of the ML market entirely.
 
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Thank you sir!

So there is a drop in barrel with a faster twist available?

The barrels on the Great Plains Hunter were 1:32 twist. The only difference between a GPR and a GPH was the twist rate. So, if you can find a GPH hunter it would be a drop in for your rifle. One might turn up on ebay. Lots of parts their because ebay prohibits the sale of complete firearms. Lots of barrels for sale.

The other option is to have one made up but it's kind of pricey. Just depends on how much you want it 😏
 
I've been looking off and on since this thread was started. If there are an barrels on Ebay the sellers don't have them listed right, GB only has 2 complete rifles showing up. Best I've found is a link to Investarms for thier version of the rifle. Have to contact them and see how to go about ordering one form them.
Muzzle Loading Rifle 160
 
A short conical will shoot fine in a 1 in 60" twist. That being said, a .50 caliber round ball, with proper charge, will easily kill an elk at traditional muzzleloading distances.
 
Hornady's PA Conical in .50 weighs 240 grains, I think, and is made for slow twists like yours. Also shoots real well in my Traditions 48 twist. It is readily available from quite a few suppliers right now. SW
I have kept that option on the table. Right now I have some .54 CVA grain conical on the way. If I push them fast enough they should do okay out to 100 yards or so. If not, then I may try the PA conical.

Heck, I doubt if the ML has more than 15 shots through it with RB, so its not even broken in yet. One of the main reasons why I purchased my GPR was to go back to shooting RB. Just have a hankering to see what it will do with a shorter conical.

Time will tell.
 
I have kept that option on the table. Right now I have some .54 CVA grain conical on the way. If I push them fast enough they should do okay out to 100 yards or so. If not, then I may try the PA conical.

Heck, I doubt if the ML has more than 15 shots through it with RB, so its not even broken in yet. One of the main reasons why I purchased my GPR was to go back to shooting RB. Just have a hankering to see what it will do with a shorter conical.

Time will tell.
You could talk to Bob Hoyt and send him the barrel . Reline with your choice of twist/Ed
 
http://www.thegunmag.com/lymans-gre...54 caliber rifles, both with 32-inch barrels.
Some good info here on twist rates of the various models of GPR. I have two of the new version, both in .50 cal. Stout rifles, more like a Browning Mountain Rifle than the previous GPR.
I paid full price for the first one, then a guy on GB had one posted up for a bit less, then dropped it to just $400 so I snagged it too, new but no box, papers.
These new ones have full one inch barrels.
Short lived project though.
 
Ball works very well, but if you want a conical try the TC Hunter 275 grain bullet.
I find it works very well with just a tad more powder than I use for a PRB and the group is good to go for deer. (I won't take any prizes off any blankets, but I whomp Bambi rather well.)
 
Ball works very well, but if you want a conical try the TC Hunter 275 grain bullet.
I find it works very well with just a tad more powder than I use for a PRB and the group is good to go for deer. (I won't take any prizes off any blankets, but I whomp Bambi rather well.)
The TC Maxi Hunter 275 grain shoot well out of my wife's .50 Hawken. Haven't tried them yet out of my New Englander. However, they are about 100 grains lighter than what I like to use.
 
I have the percussion Lyman GPR in 54. It has the slow 1:60" twist barrel. It handles patched RB's very well and does pretty good with the Lee REAL bullet (the shorter of the two versions offered). It is more accurate with the roundballs but no slouch with the REAL. I didn't work a lot with the REAL and understand using a felt underwad may have increased accuracy. In any event the roundball did all I asked of the rifle.
 
The true key is shot placement! A patched round ball has killed thousands of elk since the 1800's. Practice and make a double lung shot. Good luck.
Nit Wit

The true key is shot placement! A patched round ball has killed thousands of elk since the 1800's. Practice and make a double lung shot. Good luck.
Nit Wit
Nit wit, that is true. No argument there. However, it's not IF a RB will kill, its how far the critters run before expiring after being hit with a RB. From all the research I have done on this subject, which is a lot, I have established that big game critters that have been hit with RB's often run farther than I like to see. Much of my hunting has/is in some serious mountainous and/or thick terrain where one cannot afford to have one run far. There is no denying that conical(s), *On Average*, put big game critters down more quickly. From my own experiences over the years I have never had a big game critter that was hit with a conical go more than a few steps before falling over. That includes elk. There's just something about a big, heavy chunk of lead that's traveling a bit slower that flat out puts critters down. Not to mention the fact that a conical are better for longer distance shots.

That is not to say that many big game critters that's been hit with RB's have not expire quickly. I was elk hunting with a guy that was using a .54 GPR that shot a big cow elk. The elk pretty much fell over on the spot. I helped pack that elk out off the mountain.

IMO, closer up shots in more open country and/or less mountainous terrain would be better suited for RB's. However, everyone has to please themselves as to which type projectile once chooses to hunt with. Terrain and distances of expected shots should be a main factor. And of course, how accurate ones particular ML is with a certain projectile.

With that said, I am definitely not against using RB for hunting. In fact, one out of the three places I have to hunt is more open and not so steep. So if I can get my GPR nailed down with a RB, I do plan on using it there this fall.
 
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Muzzle loader novice, I have a very nice Lyman GPR with a 1:60 (ish) twist. I drew a Muzzle loader tag this year for a cow elk in Oregon. I'm thinking a greater twist would be better all around for this hunt.
are 1:48 or 1:24 barrels available?

Thanks all from Oregon
Just wanted to give an update, with all the great advice from you all I decided to just run what I have. Friday I was able to get to the range and develop my load. 90gr pyrodex with a patched 490 rb seemed to be the sweet spot. One of the local gun clubs does a hunters sight in at their range this time of year. Great bunch of guys and a great set up. Each bench is maned with a member and a spotting scope, you shoot and they mark a target they have at the bench with a thumb tac to show your hit. This is where I ended up at 100 yards.......should do the deed.
Thank you all for your help.
 

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He is correct. Lyman kept the GPR name when they switched to Pedersoli but so far as I know the Pedersoli ones all have Signature Series added to the stampings on the barrels. I can post pics of the examples I have but won't be able to tonight.

As far as a readily available drop in I haven't been able to find one short of a custom order from a barrel maker. I peruse Gun Broker and EBAY a couple times a week and there just isn't much stuff that pops up for them. As I stated above there are more that come up in the classifieds here than any other sites I frequent.

There is one thing to add. Invetsarms is still selling these rifles under their own model so a replacement barrel for one of those might be able to be had from them. The Pedersoli ones have been pulled from their site, the only way to find it is to search a part number from owners manual and I don't think they offer anything for them, it all had to be obtained from Lyman and they are now out of the ML market entirely.
You can buy a gemmer hawken barrel from muzzloaders.com that should drop in. You will need to swap out the thimbles, rib, ramrod spring and all that unless you buy those pets as well. I looked into it and it was well over $300 to go that route.
 
Just wanted to give an update, with all the great advice from you all I decided to just run what I have. Friday I was able to get to the range and develop my load. 90gr pyrodex with a patched 490 rb seemed to be the sweet spot. One of the local gun clubs does a hunters sight in at their range this time of year. Great bunch of guys and a great set up. Each bench is maned with a member and a spotting scope, you shoot and they mark a target they have at the bench with a thumb tac to show your hit. This is where I ended up at 100 yards.......should do the deed.
Thank you all for your help.
What is that, just a little over 2" group?
At 100 yds... ?
I'd be plenty confident hunting with that.
Good luck on your hunt too.
 

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