"Fire lapping" a round ball barrel? Fixed it!

[Roger B]

My Large Hawken barrel and I are about to go to fist city.  It was new/old stock and cuts patches consistently in one area.  I've worked the crown over very well with 600 grit and that helped.  Also used the scotchbrite method on the bore several times, but it still cuts patches.  It probably needs lead lapped, but the breech plug is case hardened and engraved and I'm not crazy about trying to unbreech it.  I'm thinking about getting one of the Wheeler bore lapping kits and using the grit for patch lube.  Probably shoot five shots, cleaning in between shots, and then go to the next finest grit until I get to 600.  Has anyone ever tried this?
Roger B.

[Hungry Horse]

Using gritty stuff for patch lube will find you pulling that breech plug for sure. A patch tight enough to do any good on your problem, will lock up in the bore, and be very difficult to dislodge without pulling the breech plug. A nearly bore size maxi ball, or Buffalo bullet, rolled between two steel plates to imbed the grit in the bullet work best. And you will have to clean after every shot, or you will end up with a stuck bullet, and need a breech plug wrench. You will have to use a charge heavy enough to insure obturation of the bullet to get bullet to barrel contact. I have done several fire lapping projects, and have to admit I started out trying just what you propose. Unfortunately I had to learn the hard way, that if a gritty patch worked the guys that built the fire lapping kits would have used it.

  Hungry Horse

[Long Ears]

I have done this but I used valve grinding compound. I found however if you use the compound on a tight patch and jag with a steel ram rod and scrub the barrel it works better. It takes a whole lot of elbow grease but it will smooth out a rough barrel. I've had to do this on a couple of Colrain barrels. They shot great afterwards. Good luck, Bob

[hanshi]

Due to an unfortunate accident and oversight the bore on my .40 experienced some rust at the breech and darkened the bore.  Using J&B paste I fired a pasted patched round through the barrel at the range.  The results of that one shot were so good I'll probably do it one more time.  Actually it probably doesn't need another but it can't hurt.

[moleeyes36]

I have done this but I used valve grinding compound. I found however if you use the compound on a tight patch and jag with a steel ram rod and scrub the barrel it works better. It takes a whole lot of elbow grease but it will smooth out a rough barrel. I've had to do this on a couple of Colrain barrels. They shot great afterwards. Good luck, Bob

A variation to this method is to use Scotch Brite instead of a tight patch.  I have the different grits contained in the Wheeler bore lapping kit that I use mostly for metal part polishing, but I've used them and Scotch Brite to lap bores.  I prefer having the different coarseness of grits available.

Mole Eyes 

[Scota4570]

It would work much better to lap it in the conventional way.  You can also lap in a little choke, and that is a very good thing.   

[Roger B]

Thanks for the thoughts guys.  Scota, I agree with you, I just don't want to bugger that breech plug getting it out.  And I would. I'm that good.
Roger B.

[Mike C]

Has anyone ever tried patching with fiberglass fabric??
Mike C

[Dphariss]

My Large Hawken barrel and I are about to go to fist city.  It was new/old stock and cuts patches consistently in one area.  I've worked the crown over very well with 600 grit and that helped.  Also used the scotchbrite method on the bore several times, but it still cuts patches.  It probably needs lead lapped, but the breech plug is case hardened and engraved and I'm not crazy about trying to unbreech it.  I'm thinking about getting one of the Wheeler bore lapping kits and using the grit for patch lube.  Probably shoot five shots, cleaning in between shots, and then go to the next finest grit until I get to 600.  Has anyone ever tried this?
Roger B.

 If the Scotch Bright did not take off the burr then there is something more profound going on or something pretty simple.  You can try some 0000 steel wool backed with a cloth patch. Needs to be tight and use with oil to it will slide. But I would not hold out a lot of hope if Scotch Brite did not work. But the steel wool may conform to the grooves a little better

Unbreeching the barrel and looking at it is the best bet. You might find something really fun like a flaw in the steel. It happens and not just in ML barrels though it more common if the low budget steels.  A friend of mine had a Bauska barrel on a BPCR and the LANDS started to flake off as soon as he started shooting it.....
Removing the breech is not a big deal if you have the right tool. For a finished patent breech I have a action wrench I built for BPCR actions that will also clamp onto a breech. Its made of 1x4 aluminum with four 1/2" bolts though I usually use only 2. Line it with tape and clamp it tight and it will pull a breech though I may have to whack it with a hammer.  The long arm of the "wrench" is only about 10" long and I use a wrench on that to turn it.
Is it cutting patches or blowing them? Shooting patches or cleaning patches? What material for the shooting patches? I have not found any ticking in fabric stores on the past few years that is strong enough for patching. How deep are the grooves? Does the patch-ball combination fill the grooves? It might be a simple answer.
If you want to fire lap it find some lead bullets like Minie or Maxi etc and a fire lapping kit. In brass suppository guns light loads are recommended but with "expansive" bullets you will need enough power to properly expand the bullet into the bore. SO I would go with 70 grains and with the solid base bullets I would use a tight fitting card wad under the bullet. Actually you can get lapping kits from Midway.
http://www.midwayusa.com/product/646612/wheeler-engineering-bore-lapping-kit.

Sorry this rambles a little but I was thinking as I typed
Dan

[little joe]

Has anyone ever tried patching with fiberglass fabric??
Mike C

years ago we were taught not to use  a fiberglass ram rod as it was abrasive to the rifleing.

[bgf]

My favorite method now is scotch brite patch loaded with polishing compound.  A 40 Cal jag works perfectly in a 50. I do 1/4, 1/2, 3/4, and full strokes, number of each depends on my assessment,  I doubt you could overdo it unless compound is really coarse, but it can always be repeated.  It is a little messy, but not difficult, and I know it works, whereas not so comfortable with fire lapping.

[longcruise]

My Large Hawken barrel and I are about to go to fist city.  It was new/old stock and cuts patches consistently in one area.  I've worked the crown over very well with 600 grit and that helped.  Also used the scotchbrite method on the bore several times, but it still cuts patches.  It probably needs lead lapped, but the breech plug is case hardened and engraved and I'm not crazy about trying to unbreech it.  I'm thinking about getting one of the Wheeler bore lapping kits and using the grit for patch lube.  Probably shoot five shots, cleaning in between shots, and then go to the next finest grit until I get to 600.  Has anyone ever tried this?
Roger B.

Roger, I have fire lapped a bunch of ML barrels and always with positive results.  Sometimes with great results.

First off, don't use anything other than a compound that is meant to be used in fire lapping.  Many barrels have been wrecked by valve grinding compound.  I have used the Wheeler Kit and the compound sold by Veral Smith at Lead Bullet Technology.  They both work fine.  The LBT is a single grit compound but still seems to arrive at a good result.  In fact, when using the Wheeler kit I've used mainly the coarsest grit and not bothered with the other two.

My first effort at firelapping was to use a patch "lubed" with LBT compound.  It does work but does most of the polishing on the surface of the lands.  It does remove the sharp edges on the lands but using a lead bullet is much more thorough.  Regardless of which you use, you need to wipe the bore thoroughly between shots.

You did not mention the caliber of the rifle but if hollow base slugs are available for it, they work the best because you don't have to load hot enough to upset the entire length of the bullet but just expand the skirt.  Around 40 grains of powder will do the job.  Most of the popular calibers have HB bullets available and for sale.  You can also buy a mold and cast your own for pretty much the same cost as the 25 bullets.

You will probably need at least 25 shots to do the job.  With fire lapping and a proper bit of crown work as often described here by Daryl you should solve the problem.

[Roger B]

I really appreciate the imparted knowledge guys.  Dan, the patching is 11 OZ denim with a .530 or .535 ball.  Hoppes Plus has been the patch lube thus far.  The patch isn't blowing, but leaving a nice longitudinal cut on the patch every shot.  I employed my thumb with 400 grit on the crown with the groups improving somewhat.  Did the Scotchbrite three or four times with a lot of prolonged elbow grease and that seemed to help.  Finally went to 0000 steel wool, but things seem to have stalled.  These are some deep grooves on this barrel, but it looks pretty smooth with a bore light.
Roger B.

[Dphariss]

I really appreciate the imparted knowledge guys.  Dan, the patching is 11 OZ denim with a .530 or .535 ball.  Hoppes Plus has been the patch lube thus far.  The patch isn't blowing, but leaving a nice longitudinal cut on the patch every shot.  I employed my thumb with 400 grit on the crown with the groups improving somewhat.  Did the Scotchbrite three or four times with a lot of prolonged elbow grease and that seemed to help.  Finally went to 0000 steel wool, but things seem to have stalled.  These are some deep grooves on this barrel, but it looks pretty smooth with a bore light.
Roger B.

Does it SHOOT accurately? If so and it does not blow patches I would not be too concerned. Just for the heck of it try putting a lubed patch in the bore (but not too wet when using a water based lube) just press it in and inch or two with a starter or the loading rod so if forms a "cup", then load the patched ball and see what the patches look like, the ones around the ball, the over powder patch will often get a hole blown through it at the muzzle. If you have a mark on the loading rod to show the ball is down remember it will stand a little high with the extra patch. See if this eliminates the cutting. If it does its not a rough bore.  If you pull a patched ball is the patch cut?  If you have gone over the bore with scotch brite and steel wool I have to think its something other than a sharp land. Could be but unlikely unless it was REALLY significant.
If the over powder patch does not cure it, given what you have done already which is the usual fix, I would want to pull the plug and look at it. OR if you know a mechanic with a scope for looking into hidden areas and cylinders you might look at ti this way. The one my son loans me has a 36" reach and will go well down the bore but will not go down a bore under about 45 caliber.
I hooked it to the TV and took this picture of a sloppily breeched 38" 50 cal barrel as it appeared on the screen. You can see into the thread of the breech by looking at the grooves.


Dan

[Roger B]

Well, that''s the problem.  It will shoot a pretty good group and then fling one out somewhere.  I suspect that is due to a cut patch.  I'll try driving a patched ball down just past the muzzle and see if that is the problem.
Roger B.

[Hungry Horse]

You capitalized the L in large when you first mentioned this barrel problem. So I assume the barrel in question is one of Bill Large's barrels. I quite frankly have never heard of a new Large barrel with a rough spot. Is this a problem that has been ongoing, or did it just develope a rough spot? Also did you get the barrel unused, or had someone else Owned/used the barrel previous to your ownership? I just feel we're missing something in this story.

  Hungry Horse

[Roger B]

I got the barrel as new old stock and it has always had this problem.  It came breeched with one of Bill's Hawken hooked breeches.  As with all of Bill's barrels that I ever owned, it has very deep grooves, and I suspect that I have a land with a particularly sharp edge.  I don't notice any obvious rough spots, and didn't see one when I initially unbreeched the barrel.
Roger B.

[Smoketown]

RogerB.,

Care to try an experiment?

1.) Pour a powder measure full of cornmeal, ground coffee, rice or similar down the barrel then, load a patched round ball like you normally would.
2.) Blow out the ‘load’ with a CO2 kit or compressed air while collecting the ejecta using an old pillow, box of old clothes or stack of old carpet scraps..
3.) Check the patch.
4.) Repeat step one marking the ball as noted below.
5.) Use a ball screw run deep into the ball and pull it manually while trying to notice if there is any stickiness along its travel.
6.) Mark the rod with a Sharpie where the sticking occurs.
7.) Check the patch.

Once I’ve started the ball to be ‘pulled’, I usually notch the ball where it lines up with the front sight that way; I have a good idea where in the barrel the problem may be.

The ball screw ‘expands’ the ball and really drives the patch into the grooves.
                                                                                                                                         
Depending on how it is breeched, the cornmeal/coffee/rice keeps the patch from hanging up and getting torn in the vent liner hole or in the flame transfer hole.

As always, YMMV.   


Cheers,
Smoketown

[Roger B]

I really like that idea!  I should have thunk of that myself.
Roger B.

[Bob Roller]

You capitalized the L in large when you first mentioned this barrel problem. So I assume the barrel in question is one of Bill Large's barrels. I quite frankly have never heard of a new Large barrel with a rough spot. Is this a problem that has been ongoing, or did it just develope a rough spot? Also did you get the barrel unused, or had someone else Owned/used the barrel previous to your ownership? I just feel we're missing something in this story.

  Hungry Horse

This particular barrel might have been made by Bill's grandson when Bill was too ill to work
and probably shortly before he died on 23 September 1985.This is only a theory but it is
a possibility.

Bob Roller

[Daryl]

Using a pure lead slug for fire lapping a round ball barrel sounds like a good idea.  It can be rolled in lapping or grinding compound, then driven down the barrel. the lube grooves filled with compound AND lube will assist in lapping as the bullet obturates. It should start out as a snug fit in the bore and a steel rod will likely be necessary for seating it. A softer charge, like 30gr. or 40gr. might also be a good idea as you don't want super sonic speed for lapping - according to the fire-lapping instructions for modern guns.

[Eric Krewson]

I have seen one product advertised and watched the video., it is called "shoot out patch lube and bore enhancer", don't know if it is any good or not. The video is impressive.

[rich pierce]

Having no experience, I wonder that fire lapping works so well.  Normally polishing of any kind involves a lot of back and forth, many passes, whereas this would pass abrasive over rough spots just once.  However, one cannot argue with success.

[Daryl]

Having no experience, I wonder that fire lapping works so well.  Normally polishing of any kind involves a lot of back and forth, many passes, whereas this would pass abrasive over rough spots just once.  However, one cannot argue with success.

Firelapping saved a slug-gun barreled rifle of Taylor's just recently. The barrel had a loose spot about 15" up form the breech - maybe 12 - it leaded badly and was not very accurate at all - 4" or so at 50 yards? Close to 100 lapping loads, with the soft bullets rolled in compound, not sure exactly how many it took. Now the bore feels even all the way out and it's shooting 1 1/2" for 5 at 100 meters off bags, using aperture sights.

[Roger B]

I finally decided that the problem almost couldn't be the lower bore, so I worked on the crown some more even though it looked perfectly fine.  I opened it up a bit with a rock in my egg beater drill and then polished it until gleaming.  I took it out yesterday and shot a neat little interlocking cloverleaf off the bench at 50 yards with 70grs 2Fg, a .530 ball, and .020 Ox Yoke Wonderlube patching.  Prior to yesterday it had just shot all over the place with the occasional fair group when the patch wasn't cut.  I hated to modify one of Bill's barrels, but it wasn't any good as it was.  Thanks again for all the great advice.  I'll tuck it away for another day.
Roger B.