View Full Version : Lapping the barrel.

July 23, 2000, 04:54 PM
O.K. now that I have my FN-FAL I figured I would call the manufacturer and get the straight on "lapping the barrel".
Said fire one round at a time, and after each round, run a bore brush and a patch with Shooters Choice Copper Solvent through the barrel. Do this ten times.
The individual said to make it easier on myself, take off the upper receiver cover, make sure the bolt was all the way forward and than fire the second round, clean, and continue until I reached the ten round marker.
Than I was to take another ten rounds and do the same thing, only this time, run the barrel every two rounds.
After I had done this, the rifle would be considered officially "lapped".
Also reminded me to either get some Shooters Choice Powder solvent or some diesel to use on the gas piston than scrub.
Question: Does this sound A.O.K.? With any of my other rifles, handguns, shotguns, I usually just took stripped them down when I first got them, cleaned and lubricated them with CLP, may be applied a little Tetra Grease, fired ~10-30 rounds through it than came home and cleaned them again with a mixture of CLP, and maybe some "Gun Scrubber".
Now I've got the heebie jeebies about "copper build up" in my rifles.
Thinking about using some Copper Solvent on the rest of my rifles and pistols.
Whadya think? Paranoid? :confused:
Never this complicated in the Army.

George Stringer
July 23, 2000, 10:07 PM
CrociJA, they aren't talking about lapping the barrel but merely breaking it in. I don't agree with their method. I break in a new barrel with the following procedure:

For the first 5 rounds--

Shoot one round. Run a wet patch (use Shooter's Choice, Hoppe's, your preference) through the bore 20 times. 10 in & 10 out. Let set for 10 minutes and repeat with another wet patch followed by 3 dry patches.

For the next 50 rounds fire five round strings and clean between each string the same way as between the first 5 rounds.

Now your barrel is broken in.


July 23, 2000, 10:39 PM

I heard the term "lapping in..." directly from the gunsmith at the local gunstore. He gave me an incling of what to do, but advised that I call the manufacturer and get their angle. I did and I feel a little more comfortable knowing that all anyone meant was "breaking in..." and not "lapping".
What really irks me is the fact that although I consider myself a novice at the basics of gun care, no one from the gunsmith to the rep. at the manufacturer told me the difference between lapping and breaking in...
Seemed to use the terms interchangeably.

Badger Arms
July 24, 2000, 01:20 AM
I'd not be overly concerned about the whole thing. Any similar method will work. The trick is to remove all of the fouling so that the rounds are bearing on rifling imperfections and not on the fouling that gets caught on the imperfections. A fire-lapping kit will work for this also and be much better at the job. In the end, be sure that all of the fouling is gone and treat the barrel with Tetra Gun per instructions. This will condition the bore and make subsequent cleanings much easier.

All things considered, there really is only a minor improvement in ease of cleaning and virtually nonexistant increase in velocity. Unless you have a Match Grade rifle, the improvements might well be lost on you. But then again, cleaning will be easier and there is the peace of mind you mentioned.