Gerat problem with Great Plains

[Dr.Doug]

I'd like some ideas and advice.

I own a Lyman Great Plains 50 cal. with the slow twist barrel. Every patch material and ball combination I use leads to shredded patches. I've used loads of 50-100 gr. of 2F, 3F, Pyrodex, and 777 with the same results.

I suspected damage on loading, but 'blowing out' a loaded charge shows pristine patches.

Lubes of different types seem to make no difference.

I can't detect any tight or loose spots in the barrel by the feel of the rod.

This barrel has about 500-600 rounds through it.

Accuracy is in the 3" at 50 yds range, but I expected it to do better. (My old, cheap, Traditions would do that at 100 yds until I wore her out!)

Thanks for your ideas.

Doug

[Mr Peabody]

Try a Wonder wad under your patch, Or try to find patch material that's woven more tightly than what your using. Both things have helped me in the past.

[waksupi]

I'll bet you are using commercial patches. Throw them away. They are trash, and sucker a lot of people. Especially if they have Wonderlube, Bore Butter, or similar concoctions on them. Get some good ol' fashioned pillow ticking, the blue and white striped stuff. This is the standard ML patch. Wash it a few times, to get the starch out. Then, find a ball that loads without use of a short starter. Always start with the patch, THEN fit the ball. Doing it the other way, results in general failure. Find yourself some water souluble machinist oil, Napa usually carryies it. Mix it one part oil, to 10-12 parts water. You can shoot all day without the barrel fouling out. Load from 70 to 90 gr. 3F Goex, and you should be good to go.

[omgb]

I had a very similar problem with mine. i fire lapped it and things improved right away. A bore scope that I just got shows lots of tool marks in the lands and grooves. I suspect that Lyman barrels are not too carefully finished. The lapping proccedure is pretty easy to do thogh it takes a couple of hours. i detailed it here so if you search the archives you should find the report.

[Dr.Doug]

Waksupi-
You suggested to "Always start with the patch, THEN fit the ball." How should I go about that? Also, "find a ball that loads without a short starter"- is that with or without a patch? A .495" ball falls from the muzzle to breach unimpeded; I'll try to find some .500" balls if you think they might help.

Regarding patches- .015" and .018" pillow ticking shreded just as nicely as the commercial patches in this gun. I've experimented with Lehigh, bore butter, Hornady great plains, SPG, mink oil, and Murphy's oil soap/alcohol/peroxide lubes. I'll try the water soluable machinist's oil next.

Mr. Peabody- I've considered an under-patch wad, but didn't see any wonder wads in 50 cal. Any experience with cornmeal? I've used it as a filler in my C & B revolvers with good results.

OMGB- I think fire lapping is on my list of things to do, just haven't had the time. Could you feel any restrictions in your tube prior to the procedure?

Thanks,
Doug

[omgb]

I did. However, the biggest issue was shredding patches, poor accuracy and terrible fouling. Check out my post "You gotta see this" in this section. that target was fired after bore lapping. It made a HUGE difference.

[waksupi]

Waksupi-
You suggested to "Always start with the patch, THEN fit the ball." How should I go about that? Also, "find a ball that loads without a short starter"- is that with or without a patch? A .495" ball falls from the muzzle to breach unimpeded; I'll try to find some .500" balls if you think they might help.

Regarding patches- .015" and .018" pillow ticking shreded just as nicely as the commercial patches in this gun. I've experimented with Lehigh, bore butter, Hornady great plains, SPG, mink oil, and Murphy's oil soap/alcohol/peroxide lubes. I'll try the water soluable machinist's oil next.

Doug

Doug, the striped pillow ticking is standard patch material. After that, you just need to try different diameters, until you find one that will load easily for you. With a patch! I know 44man and I disagree with how we load ML's, and hopefully he will also give his input. Some like to have a combination so tight as to need a hammer to get things started. Not for me. I'd rather be able to load easily for the next shot. So, try the various methods suggested, and hopefully you get things working well.

[Wayne Smith]

Just my suggestion, but go to the NRA website and go to the book section - the Firearms Classics Library. Get The Muzzle Loading Caplock Rifle by Ned Roberts, yes, that Ned Roberts (.257 Roberts). He has an extensive description of how the old target barrels were hand lapped and how the laps were made. If it was done by frontier gunsmiths with none of our advantages we should be able to do it. You need to be able to melt lead, hold the barrel relatively level, and move your arms.

No, I've not done it. I wouldn't hesitate if I had a barrel that would benefit, though.

[44man]

Yup, got to check in. From what he says, a ball and patch just blown from the barrel is in perfect shape but when fired, it is shredded. This tells me he is not damaging the patch on loading and that it is being burned by blowby.
The first thing to do is measure the bore. NOT groove to groove but from land to land. A small hole gauge is best for this. That bore might be over .500". It is best to have a ball the size of the bore with a .010" to .012" patch but a ball .005" under will work with the patch I will tell you about.
Go buy denim as close to .020" as you can find, thicker then this, say .021 would be even better. Wash it. This should be ideal with the .495" ball.
The lube you use will not matter and Bore Butter, Young Country or such should work and is not the reason for the burned out patches.
The Lyman has deep grooves as a round ball rifle should have. You are not filling the grooves and are leaving a path for gas.
Take a large strip of the lubed denim and pop a ball into the muzzle, you have to smack the starter very hard and quick, don't pull the smack. THE BALL SHOULD GO IN WITH ONE SMACK, don't stand there and pound on it! Now pull the ball back out with the patch material. Look at the ball WHERE THE GROOVES ARE. You should see material weave on those areas. The very best is to have the patch material engraved .005" into the ball IN THE GROOVES. Forget about the land areas, they are not important, they will, of course, be very deep into the ball.
If a .020" patch does not leave any marks from the bottom of the grooves, get a larger ball.
Waksupi might get away with a looser combination because his rifling is not as deep. A round ball rifle is not worth it's salt unless the rifling is .010" deep. Deep rifling requires hard starting balls. The Lyman is an extremely accurate rifle and every one I put together would make one ragged hole at 50 yd's. My friend has shot 3" groups at 100 yd's OFFHAND with one I built him.
Now then, if patches are cut up when loading the gun, then it needs lapped a little or if your balls are too hard, they are doing the cutting.

[44man]

Doug, I have to know about the Traditions you claim you wore out. Short of wallowing out the end of the muzzle with the rod, I do not believe you. Shooting patched balls does a lot of rubbing and polishing. I suspect the bore is SHOT SMOOTH. If you still have it, plug the nipple and pour the bore full of white vinegar. Let it stand overnight, wash it out and go shoot the thing as good as ever, maybe better.
By the way, this will sometimes work on a new barrel too if the lands are too sharp. It will remove the sharpness without hurting anything else. Lazy mans bore lap.

[Dr.Doug]

44 man-

Thanks for your posts. I'll try the trick with the ball, looking for the imprint of the weave at the location of the grooves, however .490 and .495 balls with patching ranging from .010" to .020" all showed the same burned patches.

The Traditions is hanging on the wall behind me. I put 4000-5000 rounds through it over about 10 years, the vast majority of which were round balls. I use a steel range rod, and am religous about using a brass bore guide. There is no visible damage to the crown. It has a 1:48" twist, and shot 385gr Hornady GP bullets into 3 MOA when new, but deterioriated to about 10 MOA when I reitred it. During it's heyday, it would shoot PRBs (.490 w/ .017" pillow tick- I'm with you, I like a tight fit!) into 6 MOA all day long. I hung it on the wall when RBs wouldn't stay inside 4" at 25 yds.

When you say you suspect the barrel is "shot smooth", what do you mean? Do you think the rifling is worn down, overly polished, or somehow fouled? Exactly what effect would the white vinegar have on it? (I like the vinegar idea for use on my Lyman barrel, but I thought after 500+ rounds all the sharp spots would be smoothed off.)

Thanks for your input.

Wayne- I've heard of pouring a lap, but have never seen instructions for it that I thought sounded complete. I'll check into Ned's book. Thanks for the tip.

Doug

[45 2.1]

I have read many times about the bore being too finely polished resulting in poorly shooting cast boolits. They would "emery" (a light lapping to roughen it) the bore and the barrel would return to shooting good groups again.

[felix]

Just plain ol' silicon dirt flying around at the riva' does a good rough up job on a barrel. 600 grit is about the smallest size you'd want. Smaller than that makes the barrel too smooth for cast especially. ... felix

[Dr.Doug]

Hummm....Too smooth...THAT'S why I come here! I'm always learning!

(Just to be clear- smooth is OK for bourbon, but bad for barrels & cast boolits- right?)

Can't wait to break out the vinegar and give it a try! (in the barrel, not the bourbon)

Thanks,
Doug

[slughammer]

If you don't have the vinegar, break out the bourbon and then pee down the barrel.

:takinWiz:

[44man]

That green Scotchbrite fit tight on a rod and scrubbed up and down will remove the shine too. For some reason the patch and ball needs some resistance and a super shiny bore won't shoot good. There is a lot of difference between smooth and polished shiny.