Frosted bore

[vviking]

What is fire lapping? A brand name of a product or a method of polishing?

A method.
A bullet embedded with progressively finer grades of grit, is fired down the bore with moderate loads.
Plenty guys swear by it.
Tubb's is the best known supplier.

Me?, never yet tried it ... very interested to hear from those who have though.

 

[points]

On a side note, a pitted bore can still sometimes shoot pretty good.

I've got an old jungle carbine, with a bore that looks like orange peel, that shoots better than most other LE's I've owned. Someone before me did a good accurizing job on the rifle, and, in spite of the look of the bore, it's a great rifle.

Quite true. I had an old sporter I picked up for parts with a very dark and pitted bore. For the hell of it, one day I put it togethr with sported parts and took her out to the range. It shot as well as any shiny bore at 100 yards.

 

[bearhunter]

A method.
A bullet embedded with progressively finer grades of grit, is fired down the bore with moderate loads.
Plenty guys swear by it.
Tubb's is the best known supplier.

Me?, never yet tried it ... very interested to hear from those who have though.

I've done this. It really depends on every individual rifle.

Some barrels with frosted bores, not only shoot well enough for what they were designed for but aren't bad foulers either.

If you are going to firelap, the kits aren't really necessary. I use extremely fine, diamond grit lapping compound. It isn't cheap but one tube will do a couple of dozen rifles.

I find it works best for firearms that are used exclusively for lead bullets.

I have used it in 303 No4 and No1 rifles with good results. Especially those with dark bores. I've also polished up different types of Mauser bores and a few Mosin Nagant bores. Usually, half a dozen rounds is plenty.

As was mentioned, keep the pressures and velocities down. I load a few grains above minimum for most purposes other than with hand guns.

I only resort to this if a rifle or handgun I want to shoot will not shoot well or if the bores are extreme foulers.

Remember, when you shoot abrasives down a bore, you are polishing the bore, which removes small amounts of material with each shot.

If the problem isn't cleaned up after 10 shots, it isn't going to go away.

 

[yes man]

Soim guessng i wouldneed hand loads too fire lap ? I think il try some jp and see how that works then take it from there as i dont hand load ..... Yet

 

[bearhunter]

Soim guessng i wouldneed hand loads too fire lap ? I think il try some jp and see how that works then take it from there as i dont hand load ..... Yet

Partner, if you're going to fire lap, you most certainly don't want to smear up the bullets on factory loads and run them down your bore. Pressures will go through the roof into very dangerous ranges. I'm talking from the experience I witnessed at our local range this spring.

A fellow there had the same idea you did. He ended up bulging the barrel on a very nice No4 MkI sporter. I bought that rifle for $65 because I had a sporter barrel in the bin that needed a home.

He used JBs as well.

JBs is at least 50% oil. Not only that, it isn't designed to remove steel. It is designed to remove copper, lead or cupro nickel fouling.

What you are planning on doing, is dangerous. You might get lucky though or you might not. Your choice.

If you insist on fire lapping, you should call a friend that hand loads. If you don't buy a kit, use cast bullets. Cast bullets are available at most gun shops. They might even load some for you. There is a very good reason why the kits are offered only to hand loaders.

Extra fine Clover Leaf valve grinding compound will work in a pinch as well.

 

[purple]

There is no need to re-invent the wheel or devise various DIY solutions for this. JB paste was designed to remove metal/powder fouling from rifle bores, and it works. Its been around for at least 50 yrs and people keep on buying and using it. The abrasive content has been calculated to do the job w/o causing excessive erosion from the bore itself. Just go buy some and follow the instructions. You will never remove the frosting/rust pits from the bore. The JB paste will remove the metal/powder fouling which accumulates in the pitting while polishing the bore to some extent.

 

[bigedp51]

The best way to clean a frosted and pitted milsurp bore is with foam bore cleaner, the less time spent with a cleaning rod in the bore the better. More bore damage is done while cleaning than any other reason and foam bore cleaner doesn't have any sharp edges.

Your not going to fire lap the pits out of the barrel, your not going to J&B bore paste the pits out of the barrel, and using a copper bore brush just eats the ends off the bore brush and gives you a false reading of copper in the bore.

Below a 1943 No.4 Enfield with a frosted bore and one shot of foam bore cleaner after firing over 100 rounds. After this two patches went down the bore and the job was done.

Spare the cleaning rod and spoil the bore.

What is amazing is the amount of blue that will come out of a AK47 gas tube and also other gas operated rifles, the combustion temperature vaporizes the base of the bullet and copper gas enters the gas system.

 

[bigedp51]

Part two

Below is a bore scope photo of a brand new Savage button rifled bore.

The throat area.

Two inches from the muzzle.

Now for grins and giggles.

A new Savage barrel before and after fire lapping.

A custom made hand lapped bore.

A Mosin after Ivan forgot to clean the bore all during WWII

Now guess what foam bore cleaner will do for your milsurp and factory rifles and spending "minimum" cleaning rod time in the bore.

 

[yes man]

Ok i never intended to smear some factory ammo with jb paste haha first and second is that foam cleaner wipe out or r they all pretty much the same?whatdo u recomend on old mosin ? I think i will do one with jb paste and one with foam see how it goes thx again everyone lots of good info

 

[vviking]

Thanks for that ^ bearhunter. Your posts are informative, & I enjoy 'em.
This thread is interesting.