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Discussion Starter · #1 ·
Been thinking of doing this for a while and thought I would run my plan past the experts first.

I have a metal lathe so thought I would turn down a brass rod with a land for some packing and a couple to hold the lead. Also thought I would let 6" or so of the rod stick out of the barrel when pouring so I had something to work with to move the slug in or out. Can also hit it with a pourch to pre-heat it.

Assume the slug needs to be at least 1/4 the twist length, and was thinking 1/2 would be better or do I need to go to 6" or so and get a full twist? At some point it won't move, right?

I have a good solection of lapping compounds from #50 to 3um plus polishing compounds (optics work). Will check the bore size first, but maybe start with 25um. Should cut real slow but I have the time. Suggestions?

I can also make guide bushing if I need to, anyone think that is needed?

Thanks

Grug
 

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Fire lapping seems like it would be a lot easier...

Not busting on you, but what are you expecting to gain from this exercise?
 
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Assuming your bore is new, or rough, shoot it several times with jacketed ammo. Clean out the copper using Sweet's 762 solvent. Dry the bore, and clean again using JB's Bore paste on a patch with a tight jag FROM THE CHAMBER END of the barrel. Lap the barrel with JBs about 200 strokes, changing out the patch every 25 strokes. While doing this exercise, avoid having the jag go all the way out of the muzzle (tape the rod so you know how far to push). When all done, make sure all the JBs is removed from the bore using patches and your favorite solvent. CAUTION: DON'T MIX SHOOTER'S CHOICE WITH SWEETS. It makes some sort of corrosive compound.

I've noticed an improvement in fouling, and subsequently, accuracy following this type of procedure. I've done it several times. Good luck.
 

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Discussion Starter · #4 ·
Thanks guys...

imashooter2, mostly the experience of doing it once. Courious what the bore shape and size are, but more for the knowledge than a known problem or concern with the gun. I will say the groups are a bit larger than I think they should but the gun is very new.

I'll shoot before and after groups and have a friend that can shoot do the same (not sure of my skill level).

Vs. firelapping, with the shop, hand lapping is easier in my case and I want to slug the barrel anyway.

Grug
 

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Anonymous said:
Assuming your bore is new, or rough, shoot it several times with jacketed ammo. Clean out the copper using Sweet's 762 solvent. Dry the bore, and clean again using JB's Bore paste on a patch with a tight jag FROM THE CHAMBER END of the barrel. Lap the barrel with JBs about 200 strokes, changing out the patch every 25 strokes. While doing this exercise, avoid having the jag go all the way out of the muzzle (tape the rod so you know how far to push). When all done, make sure all the JBs is removed from the bore using patches and your favorite solvent. CAUTION: DON'T MIX SHOOTER'S CHOICE WITH SWEETS. It makes some sort of corrosive compound.

I've noticed an improvement in fouling, and subsequently, accuracy following this type of procedure. I've done it several times. Good luck.
Guest et al,
This is my approach as well, got a rough 1894PG that's responding to a similar regimen. Shoot some jacketed, clean well, JB's with a bit of emery compounding paste mixed in for some extra cut. Shoot again.
I use a brush wrapped with paper towel, and now at the end of a polish cycle, it's starting to squeak as the steel smooths out.
I'm also relieving the barrel band and forend mount, and carefully sanding the forearm to relieve barrel pressure.
Slowly slowly is my approach here, and I've found that shooting a lot is the best way to smooth an action out.
Firelapping IMHO is way to aggressive an approach and erodes the throat.
If you want something a lil faster, leave a thin coat of JB's or cutting compound in the barrel and shoot some light loads. This has done wonders to an old Win high wall recently in 38-55 that was badly neglected, and at first looked like a candidate for relining. {:eek:)
Cheers all,
R*2
 

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Bore lapping has a new friend, fire lapping! Brownell's sells the cartridges necessary to perform this task and if its good enough for them, then it is a quality way to go. For the record, I was not too impressed with fire lapping when it initially came about, but have since come to accept it. I also am of the opinion that the old fashioned method of hand lapping a bore provides more consistent results.

If you have a one piece, stainless steel cleaning rod, you need only to equip it with a receptacle for taking the soft lead that forms the "plug". An under bore sized cleaning brush works well. You need to make a "plug" that will provide the proper volume, a wet cleaning patch, and place it inside the bore to a depth that sinks the entire length of the bristles below the muzzle. Make certain that the receptacle is centered before pouring your lead. And oil the bore prior to doing that.

The other item that you will need is abrasive powders for this purpose and Brownell's can provide that in the proper grits. Start out with the recommended cutting agent and work down to the polishing agent. You will need to make a new plug with each step down towards the final step.

The amount of back and forth draws can only be determined by the condition of the bore so no advice can ligitimately be offered there. Just be patient and do not over do the work and you should have a premium bore when finished.

Fire lapping is effective and will provide satisfactory results, but I tend to think that that process is better performed in an un-fired bore.
 
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