GPR info needed

[Cirus]

I just bought Lyman GPR from an individual but it didn't have an owners manual. What size cap, ball, and powder do I use?

 

[Zonie]

Could you tell us what the caliber is?
Without that information, we don't have a clue.
zonie

 

[almrl]

Cirus,

You can download the "Lyman Users Guide" in PDF format at:
Link

Scroll down and click on "Instructions Click Here."

The Users Guide lists max loads and suggested ball diameters. For suggested hunting and target loads you can search other posts on the forum or you can just wait a short while. Muzzleloading Forum members are more than willing to help you out.

You will still have to work up the most accurate loads for your particular rifle, varying powder load, patch thickness, and ball diameter.

Old Coot

 

[Cirus]

My bad. Its a 54

 

[Swampman]

I'd use a .520 ball, a #11 cap, and 60 grains of 3F GOEX.

 

[MikeChapin]

You can get started with some .530 balls, .015 patching, #11 caps and either FFFg or FFg real black powder. If you can't find real black in your neighborhood you can get by with Pyrodex or one of the other substitutes. I would start with a 50 grain load and move the charge up and down to see what shoots the tightest group.

You can use spit or anyone of a gillion lubs that are out there or you can buy pre-lubed patches.

For cleaning you can use a little dish soap in water to clean out the BP residue. After you dry out the barrel use Ballistol or any of the other non petroleum based lubes to preserve the barrel.

I'm with Mark in the smaller ball, thicker patch crowd but .530s and precut patching are probably going to be easier for you to find locally.

 

[bucktales]

My GPR likes .530's and .015 patches.

 

[cowpoke1955]

I have two .54 GPRs. One flint and one percussion. Both shoot excellent with .530 ball, 80 grains of FFg and pillow ticking lubed with moose milk. Use #11 caps. Like Coot said, go to the Lyman web site and you can downloan all the information you need. By the way, you made a great choice :thumbsup: .

 

[410-er]

.535 RB's,100 grs of FFg,.020 pillow gives me a real nice clover leaf at 50 yds.The .530 are good giving me about 1 1/2" at 50.

 

[greatplains]

I have an older GPR, bought it in 1989 I think, .54 cal, has a 1:48" twist barrel, which shoots TC Maxi-balls extremely well. I haven't found a PRB combination that shoots nearly as tight.

 

[Swampman]

Man those are some heavy charges.

 

[paulvallandigham]

Mark: We have to expect that new guys here will almost always be more interested in dislocating their shoulders, to prove their manhood, than in accuracy. Rhino-rolling charges are the norm for the uninformed. I agree with you, and shake my head every time I read someone else insisting on using these heavy charges.

I have an advantage. My first Large bore rifle( after starting shooting with s .22 rimfire) was a .45-70 Springfield Trapdoor, with semi-smokeless military loads shooting a 500 grain bullet. I remember how brutal that gun was on my 11 year old shoulder, and I don't abuse my shoulder like that any more. But, I was young and uninformed once, and I dreamed of shooting huge rifles, with BIGGER loads of powder, all believing it was necessary to kill anything larger than a 13-stripe ground squirrel.

Almost 50 years later, I have learned a lot more about guns. But its a waste of time sharing it with people who don't ask. :hmm: I admire your willingness to make that observation to this new member.

 

[pab1]

Some people prefer heavy bullets and connicals. I don't think it has anything to do with being misinformed. I always find the powder charge that is most accurate with the projectile being used. Sometimes it's a smaller powder charge, other times it's not. When not shooting a prb, I enjoy sending a big piece of lead down-range. To each his own!

 

[cowpoke1955]

Mark,
80 grains of FFg is not that heavy of a charge. In fact, it's a very pleasant round ball load. As for accruate, one ragged hole at 50 yards and last week I shot a 3 shot group of 3/4 inch at 100 yards. Of course this is done from a bench. After one tour in Nam and 31 years in law enforcement, please save the manhood speech for some youngster. Too old to worry about such things :blah: .

 

[lanedh]

Just my two bits, but every time I go to the range and see a newbie loading the maximum charge he can measure, and blowing his groups all over the backstop, I let him stew for a bit, then (politely) suggest that he try cutting his load in half, or less. Seeing is believing, or so they say, and it's great to see the light dawn and a smile break out when the shootist sees what his rifle/pistol is capable of without getting beaten up in the process. Once the bitter pill is swallowed with a will, it's an easy transition to trying variations in patch thickness, spit vs. goop, and all the other pecadillos that make this game so much fun. The down side of this is that I get so wrapped up in helping the newbie that I don't get to shoot enough on my own.

I don't think it's always a macho issue, I think most new shooters figure that if 50 grains is a good load, then 100 grains is twice as good.

 

[410-er]

I always try and document all variables tried.No matter how light or heavy I always settle on the tightest group.

 

[longcruise]

Paul, your and Mark's point are well taken, but for my part I don't find 80 to 120 grs of ff in my .54 under a prb to be all that punishing. Funny thing is, I started out hunting with it at 120 grains becuase it was the most accurate. Later it was down to 110 because my chrono showed that the diff with 120 was miniscule and accuracy was good enough for my hunting purposes. Lately I'm down to 100 grains for the same reasons. This year it may be down to 80 of 3f since it is adequately accurate and certainly powerful enough. OTOH, 100 grains keeps calling to me!

I have a larger issue of economy when weighing (no pun intended) heavy vs light charges and since few shots are fired hunting or preparing to hunt it's not a big deal, but most of my plinking target shooting and match shooting gets done with a .45 these days with 25 to 35 grains of 3f being suitable and plenty accurate.

The guys who are truley killing themselves with recoil are the ones I see a week before opener at the club bench sighting their stainles space guns in .50 or .54 shooting 350 to 450 grain conicals and spreading them all over the paper even at 50 yards. Watching those guns recoil and roll those guys backward while leaving their shooting glasses focused on the target, well that's a funny thing to see! :haha:

Anyway, as my old indian friend used to tell me when I was a kid, "everybody doesn't like alike, otherwise they'd all be after my squaw".

 

[paulvallandigham]

Marmotslayer; All I can suggest is that you do penetration testing as well as chronograph both light and heavy loads. You will find that within a reasonable range of velocity, that 230 grain ball is going to penetrate the same whether you shoot 70 grains of powder, or 120 grains of powder. 3Fg powder build much more pressure and has more felt recoil than would a similar velocity load of 2Fg. Since we know that felt recoil can and does affect shooting group size, reducing felt recoil give you a real advantage. That is what those shooters you describe are failing to take into account.

80 grains of 3fg is certainly going to be easier to shoot than 100 or 120 grains of 2F. But if you put that 80 grain charge over a chronograph, and then find a similar load using 2Fg powder to produce the same velocity over the chronograph, the recoil will be less. Velocity does affect barrel harmonics, even in an octagon barrel. The harmonics are not going to be as evident in group size or location, but they are there, just like in a round thin barrel. Shooting the lowest velocity that still gives you both good accuracy and the same penetration is a worthwhile goal to seek. The saving of felt recoil on your shoulder will make the difference between an unplanned, or even unexpected, flinch at the wrong time, and meat in the freezer.

 

[MikeChapin]

I always go for accuracy. I have found that most rifles have two sweet spots, one with a light load and another with a heavier load.

I also shoot a lot of competition. Shooting a heavy load all day gets rather hard on the body especially now that I'm getting older.

In both my .53 and .58 I use 50 grains 3F for 25 and 50 yard target shooting. These loads will cloverleaf off a bench at 50 yards. For the .53 I go up to 80 grains to give me the same POI at 100 yards. This will stay within 2.5"-3" at 100 yards. About as good as I can do with open iron sights at 100 yards. This load has taken a lot of elk within 100 yards. Most go right down. A few will go about 25 yards or so before they discover they are dead.

I use 90 grains 3F in the .58 to get the same bench performance. I have not shot an elk with this particular rifle but have dropped a few with a Navy Arms Hawken Hunter using 80 grains 3F behind a .562 ball.

I have never done any penetration testing even though that kind of tinkering appeals to my science background. I do go to the practical side of things. If a particular load will give me accuracy and do a particular job I use it.

 

[d.thomson]

For me also I would rather have acuracy. I use .020 oxyoke lubed with balistol water combo4 to 1 water balistol let dry over night . I have found 75 grns of 2f with .530 self cast round ball to be my most acurate load so far. This loadf will clover leaf at 50 yards. I havent had enough time so far this summer to play around with it much. F.K.