GPR max loads

[bulletman]

Is this safe to push ?, My GPR been shooting pretty good, But my best most consistent load is 110 of 3F, is this load too hot for safety ? I know lyman says 100 of 3F tops.

 

[Rebel]

The manufacturers recommended max load is normally on the conservative side because of liabilty reasons. If Lyman lists 100 gr as a max. i don't see any reason why 110 grs. would make that much difference. 10 grs in a rifle isn't that big a change, and shouldn't cause any pressure problems. :imo:

 

[bulletman]

The loads are for target not hunting. PRB 54 cal. Thanks for the info. I know its alot. This load makes a consistent one hole group at 50 yards. I tried from 50 on up to 110, with 2F and 3F, the 110 3F is best for accuracy. The 110 load come about by accident, I didnt have my glasses on and thought I was on the 100 mark on my measurer.after about 30 shots I realized what I did.

 

[Tahquamenon]

Although I've heard that the GPR loves hot loads for best accuracy, I would think that 110grain of 3FG is borderline too hot a load for the GPR, even in .54 cal.

Are you using a 10 grain increment measure? If so, I would highly suggest switching to a 5 grain measure and start over with load development.

5 grains of powder (particularily with 3FG) is a huge change.

:m2c:

 

[Rebel]

A lot of powder measurers vary by more than 5 grs. Just because it is marked 90 grs or whatever, doesn't mean it is actually trowing 90 gr. That being said, i guess i better take back my first post, since the measurer being used my be inaccurate and may actually be throwing more than 110 grs. Best to use a scale and see how close it is.

 

Although I've heard that the GPR loves hot loads for best accuracy, I would think that 110grain of 3FG is borderline too hot a load for the GPR, even in .54 cal.

Are you using a 10 grain increment measure? If so, I would highly suggest switching to a 5 grain measure and start over with load development.

5 grains of powder (particularily with 3FG) is a huge change.

:m2c:

Tahquamenon and I often disagree, but on the 110 gr. FFFG load "be'n too hot" even in a .54,..... I agree with him 100%!!

All the Lyman GPR's thet I've ever had (nearly 2 dozen) over the years, prefered powder charges of 90-110 grs. FFG (in .54) for best accuracy,.... however ther's quite a difference 'tween the pressure created by 110 grs. FFG and the pressure created by 110 grs. FFFG.

YMHS
rollingb

 

[Stumpkiller]

I have an adjustable measure that throws 132 gr (by actual measurement) on the 110 gr setting.

Even the two I have from T/C are off 4% and 6%. Your pouring methods, leveling practice & powder variations can all effect the result.

Don't assume they are correct or accurate. :nono:

 

[jim gray]

The loads are for target not hunting. PRB 54 cal. Thanks for the info. I know its alot. This load makes a consistent one hole group at 50 yards.

I find it hard to believe that your GPR won't shoot accurately with a light loads, especially if you aren't trying to keep the energy level up to an acceptable level for hunting.

I would recommend starting at 55-65 grains and moving up in 5 grain increments until you get the accuracy you want. Try with both 3F and 2F. I am certain that you can find an accurate load and save yourself a considerable amount of powder in the long run. I think that it would be a good idea for you to measure out 5 or 10 loads and weigh them to find out how accurate and consistent your powder measure is.

I still don't think that you've mentioned whether you are shooting roundballs or conicals.

 

[Tahquamenon]

[/quote]

Tahquamenon and I often disagree, but on the 110 gr. FFFG load "be'n too hot" even in a .54,..... I agree with him 100%!!
YMHS
rollingb [/quote]

Hold the phone! I've got to get my calendar out and mark this date in history!

:crackup:

Gosh Rollingb, I always though we were locked in a never-ending struggle of partisan debate versus out and out disagreement? :hmm: :winking:

 

This "Lymans" have really their own lives! My .50 GPR shoots the tightest groups with 40gr Pyrodex P! :results:

 

[Bob J]

:m2c: [/quote]

All the Lyman GPR's thet I've ever had (nearly 2 dozen) over the years, prefered powder charges of 90-110 grs. FFG (in .54) for best accuracy,.... YMHS
rollingb [/quote]

Ditto with my .54; 90 to 110 2f Goex or 90 - 100 3f. Never exceed mfgr. maximum load :imo:

 

[bulletman]

I'm using home cast 535 round balls, Denim patches from material from walmart, moose milk mix, Goex or elephant powder, cept for one can of Lidu I had. swab bore between shots with moose milk and use patches just damp with it for shooting. I did get some decent groups around 65 grains 2F, cloverleaf type, But that 110 of 3F was actually doing one hole groups, kicks like a dam mule too.

 

[cptleo1]

Seems to me 110 of 3F is pushing it pretty hard

I am just wondering if 1" smaller groups are worth the

beating that you and your gun are taking.

:m2c:

 

[bulletman]

This isnt like some ongoing thing I been doing gentlemen, Its a load I stumbled on the other day. Not something I practice on a daily basis.

 

[bulletman]

Now that I have settled on moose milk for lube, I am going to go back and start at 50 of FF, FFF. I did try 530 balls and they didnt group as well as the 535. Might try that some more too though, good reason to shoot more anyway.

 

[TomFoolerythe3rd]

My best target load for my GPR is 80 grs. behind a roundball. Otherwise I have to aim high and have the ball drop in. :m2c:

 

[bulletman]

After reading here more, and some other online Black powder places, I started this routine and it works great.
I used to settle the powder after pouring down the bore by shaking the gun or tapping it on a 2X12 I set it on. I stopped doing that now I just pour in the powder then the patch is just slightly damp, load the PRB give it 5 lite taps with the loading ramrod, then one more dry patch swab after its loaded. The groups now are more consistent for me and at various load levels too. And swab one wet moose milk and one dry patch after each shot. I see now why alot of guys use spit, I tried alot of lubes and it seems the murphys oil soap base lubes work great as long as I squeeze out the excess on the patch till its just damp with it.