Fire Lapping your barrel

[Litehiker]

I bought a NECO Fire Lapping kit several years back to smooth out my Browning A-Bolt's barrel. It did clean better afterwards. Accuracy stayed the same, excellent.

I'll do the same with my Ruger American Predator in 6.5 Creedmoor with it arrives. Rolling 5 bullets in three grits each (coarse, medium and fine) before handloading does it. Cleaning between shots is a PITA but necessary. Since I had to shoot 15 rounds anyway I used the firing process to practice my shooting from different positions.

Does anyone else fire lap their barrel?

 

[Engineering101]

Litehiker

I hate to tell you this but I ignore break in and just start using the rifle. I've got a dozen or so and they average 0.5 MOA which is about as good as I can shoot.

 

[idaho elk hunter]

I used to do it ALOT.. We had a batch of barrels from a well known manufacture come in and were receiving consumer complaints about some accuracy issues and how hard they were to clean. Most were in the 284 and a few in the 257 calibers. We ordered the"original" bullet that had a huge bearing surface on it. Fire lapped them in house at a very minimum under pressure velocity. 10 course. 20 medium and 35 fine. Anything less than this was not adequate. When we did this there were rumors floating all around that we rebuilt the rifles to benchrest standards. And that they were the most accurate rifles we ever produced from the South Gate location. People were seeking out the specific serial numbers that we lapped to pay premiums for them. Funny thing is we tested only a handful that we did, and out of them about 40 percent shot any better, only 3 did drastically better.

 

[Mikecr]

I break in with 10) Tubb's FinalFinish. And dress up lands with a couple Tubb's TMS every ~200-300 rounds. I do this with every barrel factory or aftermarket, doesn't hurt a thing.

 

[MudRunner2005]

Litehiker

I hate to tell you this but I ignore break in and just start using the rifle. I've got a dozen or so and they average 0.5 MOA which is about as good as I can shoot.

Same here.....Break-in process is a myth. The barrel will still "break-in" and your groups will tighten up, regardless of whether you shoot and clean, shot and clean, shoot and clean, or if you just shoot 5 shots, warm it up, then let it cool down completely. Which is what I do.

 

[Litehiker]

Elk Hunter,

Good to know the ratio of coarse, medium and fine rounds. I'll try that.

HAND LAPPED barrels are supposed to be what you get from custom barrel makers so I see no reason not to fire lap a barrel.

Yeah, I'm sure accuracy can be great from non-lapped barrels but a properly lapped barrel will always get copper fouled less and therefore clean up easier. And there is likely no study to back this up but I think that fire lapping may just slightly radius the land corners which can provide a better gas seal and maybe a bit more velocity.

On the other hand fire lapping may begin throat erosion a bit sooner. Hard to say.

 

[MudRunner2005]

All of my barrels (factory or aftermarket) that I get worked on by my gunsmith get professionally hand-lapped by him. They all drive tacks, too, and require minimal breaking in.

 

[barnesuser28]

All of my barrels (factory or aftermarket) that I get worked on by my gunsmith get professionally hand-lapped by him. They all drive tacks, too, and require minimal breaking in.

Does he chop an inch off of each end and recut the crown and chamber?

 

[MudRunner2005]

Does he chop an inch off of each end and recut the crown and chamber?

Factory barrels he doesn't cut an inch off, but he does cut them back enough to re-cut the chambers, and mill the old crown off, center, and re-cut the crown.

 

[barnesuser28]

So im assuming he takes enough off to remove the belling from lapping.

 

[MudRunner2005]

So im assuming he takes enough off to remove the belling from lapping.

I have no idea. I'm assuming.

He knows what he's doing, and I trust him. His work speaks for itself.

 

[Mikecr]

Sounds to me like your gunsmith is breaking in the barrels for you..

 

[MudRunner2005]

Sounds to me like your gunsmith is breaking in the barrels for you..

Sort of... He said after he hand-laps them they require very few, if any, break-in shots. He believes in the same break-in process that I do.....No cleaning and just shoot the **** out of it. Shoot it, let it cool....Shoot it, let it cool. No cleaning inbetween.

I haven't had an issue in 12 years breaking in a barrel, since I started saving myself ALOT of trouble by not wasting time with supersticious rituals.

 

[Mikecr]

The real function in break-in is to remove machined edges left by chambering. This takes relatively few shots.
The high points in rough/factory barrels? No tellin how many shots will hammer them to insignificance. That's not break-in to any procedure, but a matter to endure for maybe ~a couple hundred shots.

Either way conservative fire-lapping speeds the process. Tubb's FF leaves a surface profile matching the best in hand lapping, and it can greatly reduce copper fouling in rough/factory barrels. Here, FF can take the ~couple hundred down to ~30 without hurting a thing.
Good thing to do right before having a barrel melonite treated.