What is fire lapping?

carprivershooter · March 23, 2011, 11:40 PM

I have a rifle that is fairly new and the bore is has a dull finish. I have cleaned it with Hoppes 9, Rem Oil, CLP and the bore is still dull and the patched continue to come out with some black. So will fire lapping polish the bore. ( the lands or groves have a dull shine). The rifle is and M1 carbine by Auto Ordince.

Ideal Tool · March 24, 2011, 12:25 AM

Hello, carprivershooter. Fire lapping is done by forcing an abrasive grit into the surface of a bullet, either lead or jacketed, and firing a with a VERY light charge of fast burning powder. I have done this with an original 1898 Krag rifle, & 1903 Sprgf. The problem is that if not careful..the throat can be lengthened. Also, groove dia. can increase. In my case, the bore was loose about 6" forward of chamber..this was common with turn of century military arms from powder erosion. F.L. cured problem, brightened up bore, even grooves, very very slight taper..measured in tenths of thousand. Accuracy greatly improved.
That said, I don't think you need, or should use such a drastic procedure on your rifle. Have you tried JB compound on a tight patch as per instructions? And after that, some JB Bore Bright..this usually will brighten things up nicely. Just be sure to use a good quality cleaning rod and rod guide. Best of luck!

FrankenMauser · March 24, 2011, 02:10 AM

Fire Lapping shouldn't be done for cleaning purposes.

Scrub. Scrub. Scrub.

As long as the patches are coming out black, that bore is dirty.

M.O.A. · March 24, 2011, 03:22 AM

it might be that your gun has had molly bullets shot through it or the bore is molly coated

if so its going to take a lot of cleaning

Rifleman1776 · March 24, 2011, 09:33 AM

How does it shoot? If good, leave alone.
If not accurate, re-read the post by Ideal Tool and follow advice given.

tpcollins · March 24, 2011, 09:47 AM

I've done this procedure to a new .22 and a new .50 caliber muzzleloader - they both shoot really great. (The .22 is rediculously accurate at 50 yards). I have a new .204 that I will do this to as soon as I get a small enough rod - good luck.

http://www.centerfirecentral.com/lapbore1.htm

carprivershooter · March 24, 2011, 10:14 AM

I thank everyone for their comments. I will first try the J B Bore Bright. TFL is a great place to ask questions. There is such wealth of information in this group of people thank you again.

Bogie · March 24, 2011, 05:17 PM

Doesn't sound like moly...

I'd soak it with a good penetrating oil, and patch it out once a day for a bit... Thing is, it's probably not going to ever be a "shiny" bore unless you screw in a new barrel.

March 23, 2011, 11:40 PM	#1
carprivershooter Senior Member Join Date: February 16, 2008 Location: Michigan, Upper Pennsula Posts: 396	What is fire lapping? I have a rifle that is fairly new and the bore is has a dull finish. I have cleaned it with Hoppes 9, Rem Oil, CLP and the bore is still dull and the patched continue to come out with some black. So will fire lapping polish the bore. ( the lands or groves have a dull shine). The rifle is and M1 carbine by Auto Ordince.

March 24, 2011, 02:10 AM	#3
FrankenMauser Senior Member Join Date: August 26, 2008 Location: In the valley above the plain Posts: 13,773	Fire Lapping shouldn't be done for cleaning purposes. Scrub. Scrub. Scrub. As long as the patches are coming out black, that bore is dirty. __________________ -Unwilling Range Officer -Unwilling Match Designer -NRL22/PRS22/PRO -Something about broccoli and carrots

March 24, 2011, 10:14 AM	#7
carprivershooter Senior Member Join Date: February 16, 2008 Location: Michigan, Upper Pennsula Posts: 396	thanks for the help I thank everyone for their comments. I will first try the J B Bore Bright. TFL is a great place to ask questions. There is such wealth of information in this group of people thank you again.

March 24, 2011, 12:25 AM	#2
Ideal Tool Junior member Join Date: October 6, 2010 Location: Michigan Posts: 1,080	Hello, carprivershooter. Fire lapping is done by forcing an abrasive grit into the surface of a bullet, either lead or jacketed, and firing a with a VERY light charge of fast burning powder. I have done this with an original 1898 Krag rifle, & 1903 Sprgf. The problem is that if not careful..the throat can be lengthened. Also, groove dia. can increase. In my case, the bore was loose about 6" forward of chamber..this was common with turn of century military arms from powder erosion. F.L. cured problem, brightened up bore, even grooves, very very slight taper..measured in tenths of thousand. Accuracy greatly improved. That said, I don't think you need, or should use such a drastic procedure on your rifle. Have you tried JB compound on a tight patch as per instructions? And after that, some JB Bore Bright..this usually will brighten things up nicely. Just be sure to use a good quality cleaning rod and rod guide. Best of luck!

March 24, 2011, 03:22 AM	#4
M.O.A. Senior Member Join Date: January 29, 2011 Location: south indiana Posts: 555	it might be that your gun has had molly bullets shot through it or the bore is molly coated if so its going to take a lot of cleaning

March 24, 2011, 09:33 AM	#5
Rifleman1776 Senior Member Join Date: April 25, 2010 Location: Arkansas Posts: 3,309	How does it shoot? If good, leave alone. If not accurate, re-read the post by Ideal Tool and follow advice given.

March 24, 2011, 09:47 AM	#6
tpcollins Senior Member Join Date: February 18, 2009 Location: SE Michigan Posts: 558	I've done this procedure to a new .22 and a new .50 caliber muzzleloader - they both shoot really great. (The .22 is rediculously accurate at 50 yards). I have a new .204 that I will do this to as soon as I get a small enough rod - good luck. http://www.centerfirecentral.com/lapbore1.htm

March 24, 2011, 05:17 PM	#8
Bogie Senior Member Join Date: June 6, 2000 Location: Job hunting on the road... Posts: 3,827	Doesn't sound like moly... I'd soak it with a good penetrating oil, and patch it out once a day for a bit... Thing is, it's probably not going to ever be a "shiny" bore unless you screw in a new barrel.