Barrel lapping- worth the effort?

[QuarterBoreGunner]

Ok so here’s the scoop: I’ve always handlapped the barrel of any rifle I picked up used. Never did it to new rifles and especially never to ‘match’ quality barrels.
The process I use is pretty simple; JB Bore Compoundâ„¢ impregnated into a cleaning cloth and then wrapped around a Parker Hale type jag. Then lap the barrel in six-inch lengths until complete. Then lap the full length of the barrel, for about ten strokes. Always from the breech. Does this sound right? Or have I been completely destroying my barrels?

I’ve never fire lapped a barrel- if I understand the process correctly, a lead round is rolled in the lapping compound and then fired. Is this repeated?

And has there ever been a definitive study done to prove that lapping a barrel, either by hand or firelapping, actually makes a noticeable difference?

 

[Watchman]

There are varying opinions on this, some good some bad.

I fire lapped a Colt Anaconda. I frst fired a a couple of boxes through it when it was new, it seemed to lead up quite a bit. After reading an article posted in Guns and Ammo magazine several years ago, I decided to try it.

It did polish the barrel and make it easier to clean. It also improved the groups with the loads I was shooting, in this case some 245 LSWC running right at 1000 FPS.

I used unsized,unlubed bullets rolled in lapping compound. IIRC, I used a a couple of grains of AA#5. You want the bullet to just leave the barrel, no need for speed.

Then you must completely clean the barrel.

I think the the effect is more on a barrel that is rough to begin with. Really, all you are doing is speeding up the natural prossess' that occurs after shooting several hundred rounds.

BTW, I ve read all of your links on the 300 whisper. Intresting site you have there, great job. As a matter of fact, I bookmarked it.

 

[Catshooter]

QB,

I have used the original Firelapping compound on a number of firearms, with mixed results.

An FR-8 with a dark bore - excellent, groups cut by 75%

A Kel-Tec Sub-9 - about the same as the FR-8

Marlin M60 - this puppy will do about one inch at 100 yds now.

It's not a process you need to do with a match bbl, but with bbls that have room for improvement it can really help.'

Oh yes, I did '42 vintage High Standard HD. Before, with Federal Gold Medal - 65' = about 3.5 inches. After, with rounds out of the same box - 65' = about .75 of an inch.



Cat

 

[Guyon]

You folks might want to read some of Gale McMillan's back posts over on TFL.

 

[Matt G]

The late Gale McMillan's posts about lapping at TFL were mostly regarding fire lapping. He didn't see any point to it. That said, he didn't fire lap because he (or someone acting on his behalf) did hand lap every barrel that left his shop. I gathered that he felt that a judicious amount of hand-lapping in a new raw bore was helpful.

If you've ordered a rifle from a non-custom company, it might well be worth it.

BTW, on a side note, even if you don't hand-lap or fire lap your brand new barrel, please do thouroughly clean your new barrel before firing. When I first got my excellent Remington Sendero, I was getting stainless steel shavings out of that thing even after several patches. I'd hate to have had those travel down the barrel at 3300 fps!

-M.

 

[Watchman]

You folks might want to read some of Gale McMillan's back posts over on TFL.

I did.

He also makes the point that custom barrels, such as his, didnt need them and he discouraged the practice.

However, he also aknowledged that factory barrels and one that were rough in general, could benefit from it.

In any case, I cant argue with the results on my own gun.

 

[Art Eatman]

I don't think folks deny the effects of burnishing. Gale snickered at the idea of shooting, say, 200 rounds as "break-in" before normal use. Few people shoot benchrest competition with an off-the-shelf rifle, but off-the-shelf rifles are plenty good for hunting--they just get better with use.

I don't understand the benefits of "shoot one, clean; shoot another, clean..." Get the new rifle sighted in. Then do some normal cleaning to get it in the "Early in the morning" condition you'd have when you go to the range or the deer stand. Then fire for record so you're sure of your sight-in...

, Art

 

[zahc]

Don't you know, lapping barrels removes the fingerprinting. No honest man would ever want to lap a gun barrel...

 

[4v50 Gary]

If you get a custom match barrel, why bother lapping it? It's the factory bores that may need lapping - especially if it isn't shooting too well.

 

[sanchezero]

Damn zahc,

You must either have really small fingers or be shooting HUGE guns. There's no way I could put fingerprints in my barrel.

 

[Gewehr98]

QuarterBoreGunner, one question, if I may...

Did the guns need lapping? If so, what indications did you have that they needed it?

(From the "if it ain't broke, don't fix it" school of thought)

 

[bogie]

"polishing" the bore with JB compound won't do a lot to the rifling, etc...

HOWEVER, with a used/surplus rifle, you'll likely see an improvement, since the JB will probably go a long way toward removing copper buildup.

 

[Mike Irwin]

A qualified maybe.

I've seen some guns show pretty dramatic increases in accuracy potential, while others haven't responded nearly as well.

You never know until you do it, but in general I really think the process is worth the effort, especially now that fire lapping makes it so much easier.

 

[ShaiVong]

So you take this JB stuff and put it on a cloth, then push it through the barrel to polish?

And you use a jag?

Here comes the ignorance. I've seen jags, ive heard of them, but i never understood their use or application. I guess its to grip a cloth eh?


Might be worth trying on my Enfield N4 M1

 

[Mike Irwin]

A jag doesn't really grip the cloth, it forces it through the bore and pushes it into close contact with the lands and grooves. You get a more effective cleaning that way.

 

[Black Dragon]

My father-in-law fire lapped an AR10 with group of bullets from (can't remember the first name)Tubbs. This guy is a world class target shooter. Well, the lapping seemed to work great for him. His AR10 get subMOA every time (Ave. 0.75). So I tried it on my AR10 and I get (on average) about 0.90 MOA. The fire lapping didn't seem to do much for my AR15 (good or bad). Also, the barrel of the AR10's might be shooting that well inspite of the fire lapping.
Life in the big city. Just my $0.05 (inflation)

 

[Mikul]

I read an article on firelapping in some gunrag about a year ago. They cleaned the rifle, ran a borescope down it and it showed all of the scrapes and irregularities in the bore. Then they fire a series of groups with the rifle to get a baseline.

Then they firelapped the barrel, cleaned it, and ran the borescope down. What a HUGE difference. It looked like it should: nice gooves and no nasty scrapes. The group size was cut ALMOST in half. This was across a series of 5-10 5-shot groups, not just on one group.

I was sold. I have the bullets, but I'm working on other issues with my rifle first... like headspacing.

 

[Duke of Lawnchair]

Do you folks know of any loaded cartridges impregnated with the lapping compound?

 

[Steve Smith]

http://www.zediker.com/tubb/finalfinish.html

From G. David Tubb.

Not Tubbs.

This is G. David Tubb:

This is Tubbs:

I'm sure Dave would appreciate it if you got it straight. Tubbs would too.

 

[QuarterBoreGunner]

OK, lots of good info here, many thanks all around. I suppose until I see evidence to the contrary, I’m going to keep hand lapping my bores. As I said I only do this to questionable rifles; that is, something I’ve picked up used or milsurp. Never have done it to a match quality barrel (i.e., my Weatherby .22-250 SVM with the Krieger™ Criterion™ barrel).

Here’s another question; I’ve heard of people using JB Bore Compound™ as a regular cleaning product. I know the abrasive in JB is a pretty mild rouge compound, but would constant use during the cleaning process be harmful? I’m interested in it since it would seem to negate the need to use chemicals like Sweet’s 7.62 to remove copper fouling (an exercise I REALLY detest).

BTW, I ve read all of your links on the 300 whisper. Intresting site you have there, great job. As a matter of fact, I bookmarked it.

Watchman- I think you may have me confused with someone else; I’ve not done any work on the 300 Whisper, though it sounds like a fun cartridge.

Thanks anyway for all the info!

 

[Jon Coppenbarger]

gotta clean at least one and most likely both of my rifles tonight before the matches this weekend.
then both will get a heathy dose of bore pasting before the nights out.
those things are gonna shine.
my barrel I use moly in has not been cleaned in around 300 rounds as is right there but its time to start over on it. gotta keep a eye on it as it has over 5,000 rounds down it.
it will get the most work tonight as I plan on getting most of the moly out of it in case my #1 rifle goes down over the next few weeks.
my #1 rifle will get a very good going over and alot of bore paste strokes tonight also and it will get the best of everything done to it.
let me see tonight load about 200 rounds, clean rifles and oh some laundry, I think pizza and another couple of episodes of band of brothers ought to take care of the evening.

 

[Steve Smith]

Jon, sounds good. We'll have a JB/Band of Brothers party tonight.