Abrasive Bullets

[MangesMade]

Peashooter, are you there?   Many Moons ago I read about these cartridges that had abrasive bullets, seems you start out with say 220 grit, then 400 grit and finish with 1200 grit cleaning inbetween, before firing the next grit, to smooth the burrs out of the barrel.
    ANYBODY EVER USE SUCH A PRODUCT?  How do they work?

[Fred Flinstone]

That's the proper term, in case you don't get a response, try it.
---Fred---

[peashooter]

Yes, there is such a thing out there. Not many people have used them I don't think, but it sounds like a gamble. For some it helps, some don't notice any difference, and for some people accuracy is worse after the fire lapping. You would not to lap a custom, or very high quality barrel since it is probably finished about as good as it ever will be, and in your attempt to smooth it out(the purpose of lapping) could actually make it rougher. I'm not much of a gambler, so I wouldn't try it on a rifle that's shooting okay. If I had something that shot terribly, and didn't mind if it made it worse I might try it. But I'd      to turn a good barrel into an inaccurate one. You might want to go over to rimfirecentral.com and look at the CZ section. There was a question on fire lapping a week or so back. One guy tryed it with his American and noticed an improvement.

peashooter

[snapshot2]

The process is called fire lapping. You will find abrasive imbedded bullets available at brownell's. Although I feel the wisdom of this technique on modern bores is questionable, I am trying it. The kits for this purpose are pricey. I have used valve grinding compound with questionable results, and am now finishing with JB Bore Shine. I will post my biased opinion when finished.

www.brownells.com/Product/index.asp

[Fred Flinstone]

After looking back at my post I saw it could be baddly interpreted, what I ment by:'' try it'' was: if no response, and not physicaly trying it on rifle. Before doing such an operation one should have the barrel examine with a borescope as to see the condition of twist, area of free-land(bore),etc..Only after this confirms rough spots should one attempt this. Don't go and jump on every new bandwagon there is or you'll end up with a ruined gun.

---Fred---

[Unregistered(d)]

I've fire lapped a 10/22 factory barrel that wasn't shooting, and afterwards it still didn't shoot well.  However, it wasn't any worse, and it fouled noticably less.  Most kits (mine is made by Wheeler) come with coarse to fine grit.  I only used the fine grit, about 20 bullets, and finished off with 20 bullets coated with JB.  I don't think you'll hurt anything by trying it, but don't expect fantastic results.

[MangesMade]

Thanks for all the replies...If my new CZ shoots the rest of it's life as well as it did it's first 5 shots, I don't think I'll be needed to do anything to it but practice...But having the barrel checked with a bore scope was a good idea.   Thanks,
             Mike

[snapshot2]

Manges, think there is some good advice given here. The "if it ain't broke, don't fix it" adage applies to the barrel bore. Honestly, I don't see how any modern barrel will be improved by the process called fire lapping. If it shoots that bad to begin with, better to rebarrel. I am experimenting with the process to see if it will make tight groups even better. For good or bad, I am a obsessive tinkerer. This obsession has gotten me into more trouble over the years. After finishing my barrel with the JB Bore Shine, I will give a bench report. Thus far, several types of ammo have been fired. My best results, by far, have been with Winchester Dynapoints. Federal Gold Metal Match 1080fps @ nearly $9. a box were nearly identical to the Dynapoints. With the cheap ammo I had several 5 shot groups covered by a dime, and one the size of a .30cal round. This was at 50 yds! Of course, some groups were ruined with fliers. Some were me, and others were the ammo. If reports are correct, and Dynapoints no longer being manufactured; I will try Powerpoints. I still have 6, 500rd boxes of Dyna's left. Ooh..did I say the Special so impressed me, I had to have an American. Should be here in about a week. Good shooting!

[OldCorpsJoe]

The kit is called "Final Finish" from David Tubbs and available from Lock, Stock & Barrel.  Consists of 50 rounds of specially loaded, very low velocity .22 LR ammo, five lots of 10 rounds, #1 through #5, each imbedded with a progressively finer abrasive compound.

With a bore as finely finished and as tight as the CZ's, I would definitely avoid numbers 1 & 2 and begin with 3.  It really slicks up some not-so-well-finished bores, keeps them from leading up as quickly.  It's good for older guns with rough bores, especially if you follow up with some of J.B.'s  Bore Paste and/or Bore Polish, then maybe a little Flitz for a final touch-up.

Joe