Question about Lyman GPR barrels

[OB OBrien]

Found a Lyman GPR 50 cal 1 in 60 twist at Midsouth. Question is will this barrel drop into my Investarms 50 cal hawkin? How about the sights are they interchangable?
Thanks OB

 

[cowpoke1955]

Investmentarms Hawkens, like those sold by Cabela's and Dixie, uses only one wedge pin and the GPR uses two. The Investmentarms Hawkens adjustable rear sight takes two screws and the Lyman GPR has a dove tail.

 

[OB OBrien]

OK thanks. So what company makes a barrel that will drop in my Investarms 50 cal for shooting round balls? Is there a 45 cal that would drop in?

Thanks for all the help, this forum is great.
OB

 

[cowpoke1955]

Check out Green Mountain barrels: http://www.gmriflebarrel.com/ . Good luck :thumbsup:

 

[cmdrted]

GM is heavily back ordered but check out thier find a dealer page and call around, alot of thier products are sitting in dusty corners of alot of these shops, I found a 50 40 45 just by calling those dealer referrals. The usual internet sources have been tapped out for awhile!

 

[Swampman]

The GM drop in barrels are designed for the T/C Hawken. They may not drop fight into your gun. It should shoot round balls just fine with the barrel that's on it.

 

[Robert58]

Dixie Gun Works says that their Hawken has .010 deep cut grooves. Check your barrel and see if your barrel has the deep cut grooves. If it does, you will not get very much improvement going to 1 in 60 twist. The original Hawkens Rifles had 1 in 48 twist with deep cut grooves and they were known for their accuracy. I believe that, only The Thompson Center Hawken has the shallow grooves designed for Conicals.

Robert

 

[OB OBrien]

OK Mark and Robert. I had been led to believe I needed a 1 in 66, 70 or 72 twist for accurate round ball shooting. My Investarms Hawkin was bought new way back in 1976 or so. (Does that make it PC ? (lil grin)). I just miked it out and the barrel does have .010 grooves. I also just checked the twist and it's 1 in 48. So I guess I'm good to go with round balls.

This brings up another question, How good is this gun for shooting saboted 45 cal HP bullets, and mini bullets, say the 370 grain ones, for hunting?

Thanks again to all you good folks in getting me back up to speed. I'm loving it.
Cya OB

 

[Swampman]

It will shoot sabots just fine. The guys on the MM forum do it all the time. The groups they get are amazing.

I'm not sure about Minis & Maxis.

 

[paulvallandigham]

Sabots normally need a faster rate of twist- like 1:28. You ask about conicals that have bands and are long. They will normally not stabilize in a 1:48 ROT, much less in any ROT that is slower. Those long bullets need a fast ROT like 1:28, or 1:20.

The 3 ROT barrels you have mentioned were designed to shoot mainly RBs, but can shoot very short conicals, like the Lee Precision,R.E.A.L. bullet.

You sound like someone who doesn't have a clue what a RB that diameter can do on game, and are working with a bit of information about bullet formance you gained from being around modern high speed cartridge guns. Those are apples and oranges compared to BP ballistics. When you get to .54 caliber and larger bore sizes, the RBs are so haavy that the Normal result of shooting any game is for the ball to completely penetrate the body, and leave some of its energy on the ground behind. Its an exception to the norm to find any part of a RB still inside the body of game.

With a .50 caliber, you can expect the RB to completely penetrate deer sized game, because they are thin-skinned and have very small, soft bones. Most deer are shot well within 100 yds- in fact, most are shot under 50 yds. At those ranges a 50 caliber RB will go through most deer.

So, there is no need for you to be searching for huge conicals and barrels to shoot them. If you want to hunt bear, or Moose, buy a .58, or .62 caliber rifle. Those RBs will bring down any bear or moose that walks the earth. Those balls may be a bit of an " overkill" on deer, if there can ever be said to be such a thing.

 

[Zonie]

While admiting that I haven't followed the users of sabots my impression is that they do not work well with deep rifling grooves, or in slow twist barrels like a 1:48.

Perhaps a really short pistol bullet in a sabot would work but the longer ones need to spin at a very high speed to stabilize which explains why the barrels that are made for shooting saboted pistol or rifle bullets have very fast rates of twist and very shallow rifling grooves.

 

[renovato]

For deer hunting, a .50 round ball is plenty. No need for conicals. Your 1:48 barrel should shoot round balls fine. I have the .54 Investarm Hawken and it's a very accurate gun with round balls.

 

[Dphar]

OK Mark and Robert. I had been led to believe I needed a 1 in 66, 70 or 72 twist for accurate round ball shooting. My Investarms Hawkin was bought new way back in 1976 or so. (Does that make it PC ? (lil grin)). I just miked it out and the barrel does have .010 grooves. I also just checked the twist and it's 1 in 48. So I guess I'm good to go with round balls.

This brings up another question, How good is this gun for shooting saboted 45 cal HP bullets, and mini bullets, say the 370 grain ones, for hunting?

Thanks again to all you good folks in getting me back up to speed. I'm loving it.
Cya OB

With that groove depth and a decent patch fit it will shoot well with PRB and 90 gr of FFFG in all likelyhood and more powder than this is a waste.

In a 50 I would prefer a 48 twist.
You do not need the saboted pistol bullets, its very likely they will not perform better than the rb. The Maxi is notorious for not expanding.
The 50 caliber RB is near ideal for shooting deer sized animals and will kill them dead to farther than they should be fired at.
The sabots and elongated projectiles simply add problems that to me out weight their usefulness.
For example the typical 240 gr 44 cal soft point/hollow point is not the panacea as a handgun hunting bullet and many hunters, especially in bear country, shoot hard cast bullets of 250 -300 grains from 44 mags to assure penetration. Something the lighter jacketed pistol bullets, designed for massive expansion, are not renowned for.
The maxi and its kin have a rep of moving off the powder. Not a real selling (the important thing) point but it gets little press it seems.
Shot placement is far more important that the slug you shoot in most cases.

Dan

 

[Swampman]

I wouldn't exceed 70 grains of 3F. The Sabots will work fine if you wish to use them. I'd try the T?C Cheap Shots first. Power Belts are accurate too but I don't like them.

 

[smo]

Good advice Mark , the two investarms i own like 65 grns. in 50 cal. Anything more the groups start to open up quick.