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Bazoo
07-27-2020, 04:57 PM
I'm looking to fire lap my revolvers to remove constriction at the threads. I've read this https://gunblast.com/FerminGarza-Firelapping.htm . I've read Jacketed Performance with Cast Bullets by Veral Smith. Of course I've read Fryxell's from Ingot to Target.

I have ordered a copy of Beartooth Bullets Technical Guide but haven't received it yet.

Now I'm looking for direction towards other literature or articles in regards to firelapping.

Some years back I purchased a Wheeler Bore lapping kit, I find it's instructions lacking.

Thanks for some more direction.

Bazoo

curdog007
07-27-2020, 07:00 PM
The Beartooth Bullets guide will tell you what to do. Worked for me.

DougGuy
07-27-2020, 07:18 PM
About 30yrs ago I had no idea what firelapping was and even less how to do it. I had heard of it, maybe a Taffin article in the trade rags, can't remember now. There wasn't any home internet back then, no Google, so I just figured out what might work and did it. It worked!

I took 50 commercial hard cast K type LSWC boolits, boiled the hard crayon lube off them, the gun shop next door had a broken bottle of JB bore cleaner on the shelf that had been sitting for years, I got that and poured all the oil off. I loaded the boolits in some excessively flared 45 Colt cases over 8gr Unique, stopped when the lube groove was at the case mouth, and I used a small wooden stick to cram the bore cleaner into the groove all the way around, then seated and crimped all 50.

Next day at the range, wh00ee was there ever a ton of smoke, I fired all 50 in a Blackhawk, careful not to touch the outside of the gun (which was covered in fine oily abrasive) as I reloaded, took it home wrapped in soft cloth and cleaned it. I was amazed at how smooth and shiny the bore was, I could tell a big difference just by eyeballing the rifling held up to a light, it cut groups in half by doing this. It didn't dull the rifling, but it sure polished the grooves considerably.

Now, back then I didn't have pin gages, didn't even know what thread choke was, I had a convertible with .456" throats, sent this back to Ruger and asked them for .4515" throats which they happily obliged on their dime. Once the throats were corrected for .451" bullets, and the bully-ish firelapping was done, it easily out shot me, and that's back when I had good eyes and could put a whole box of 45ACP through a 1" hole at the range.

I have not tried the low dose version where boolits are rolled in abrasive, I think my method would work quite well although I wouldn't load them up nearly as hot had I the need to do this again.

Piedmont
07-27-2020, 08:02 PM
I've done many revolvers, too. Never had pin gauges but they would be nice. I think I started around 1986 and at first used JB bore compound in the groove like Dougguy , but with a reduced powder charge. Then LBT kit and Veral at first recommended putting it in the bullet groove. A little later rolling between two plates to imbed the compound in the bands of the bullet came along. I don't think you need pin gauges to do it. You can watch the cutting action happen. Clean frequently. The cutting happens only at the constriction and for a long time that is only place you get a change.

If you roll too much abrasive in your bullets they will get so large they won't chamber. If you do that you'll figure it out. It is easier to use cases that haven't been resized. Reprime, bell slightly and seat your bullets. You need enough powder to get the bullet out the barrel, but if they are only going 500 fps that is plenty to lap your barrel.

It is not hard to do, just time consuming.

Bazoo
07-27-2020, 08:46 PM
I appreciate the replies.

I would think that you could roll a lubed bullet to embed polishing compound and it would still cut, primarily at the beginning of its entry into the barrel. Then the lube would start flowing and lessen the affect to some degree. I wonder if this would permit less leading?

Texas by God
07-27-2020, 11:24 PM
Ross Seyfried wrote a good article about fire lapping in G&A magazine decades ago. And G. David Tubb sold a fire lapping kit for rifles. It is more fun than hand lapping, that is for sure.

Sent from my SAMSUNG-SM-G930A using Tapatalk

Mr Peabody
07-27-2020, 11:27 PM
I've have very good results with Marshall Stantons' fire lapping routine. Both rifles and revolvers shot much better after using his products, even my c&b .44 did better.

DougGuy
07-27-2020, 11:27 PM
Ross Seyfried wrote a good article about fire lapping in G&A magazine decades ago.

That might be where I learned of it. I remember it was many many years ago.