Thread: Lapping barrels

So what is the best method of doing this ?? .I have read threads ,articles and talked with others . Some use steel wool. autosol. jb paste ect . Have watched Nathan Fosters vid which seemed very sensible but at odds with other methods and views. So what is the correct way . Having read Bos's thread, should apart from a good cleaning method be necessary on what is a high end barrel . I can understand it on a remington /cheaper barrel which is not as well made . Curious on your thoughts as to which method and to which barrels need it and those that dont .

Akaroa 1 knows all about it. From my limited understanding 'lapping' means using a lead 'lap' that is cast in the barrel. Other methods are just polishing.

@wayno what are you trying to achieve and why do you think you need to lapp ?

My understanding of the lead lapping process is it does polish, of course, but polishing can be achieved in many other ways. The unique thing the lead lapping does is to make the bore and rifling uniform throughout. It is intended to turn a cone into a cylinder.

So if, as is common, your muzzle-end is a bit shot out, that's only a problem because it widens out from the rest of the barrel. You can have a wide long throat and the rifle may still shoot well, but a widened muzzle end is never good. The lead lap is cast at the muzzle and will make your bore (lands and grooves) uniform 'shot out' depth throughout the barrel. It will make sure all the barrel is like the muzzle, because so long as ALL the barrel is uniformly 'shot out diameter' there's no problem.

It's really a procedure for very pitted / shot out milsurp barrels, not for improving fine target barrels. I have a few .303 barrels awaiting their day of resurrection that way.

Most high end barrels are lapped before being fitted, The only reason to lap a barrel is if it has a bad copper fouling problem
then i would have words with whoever fitted and chambered it,
Doing a lapping job yourself is a bad idea on an expensive barrel when you don't know what you are doing you could make the problem worse.

Originally Posted by wayno

So what is the best method of doing this ?? .I have read threads ,articles and talked with others . Some use steel wool. autosol. jb paste ect . Have watched Nathan Fosters vid which seemed very sensible but at odds with other methods and views. So what is the correct way . Having read Bos's thread, should apart from a good cleaning method be necessary on what is a high end barrel . I can understand it on a remington /cheaper barrel which is not as well made . Curious on your thoughts as to which method and to which barrels need it and those that dont .

The lead lap is to ensure you lap to the same depth throughout the barrel, using steel wool as a brush will polish, but at varying depths, basically hills and valleys will be polished instead of getting evened out, the lead lap will focus the grit on the hills.

Probably used the wrong term , i have a rem factory barrel that has some rough spots about an inch from the muzzle end and im wondering if they are causing the groups to be a bit bigger than you might get if they were not there 2inch at a hundred. That said it is a mountain rifle contour so i dont shoot more than 3 shots at one go as she heats up and starts biffing them around . I am using hornady 150 eldx factory ammo at the moment ,i have not started to hand load yet . I removed all the copper from it but have yet to return to the range to see if that was the main problem .

I wouldnt go doing to many things at once. Try shooting it first after your clean. Have you tried different ammo in it

I did try some 162 loads that worked well in my last 3 remingtons of the same cal but no it didnt like them or my 120 load which again worked well in the others the only difference is the barrel contor the other 3 where all BDL'S and had a thicker barrel . Ill sort it but was just wondering as it seems to be a thing that people suggest to sort remingtons out .

Originally Posted by wayno

I did try some 162 loads that worked well in my last 3 remingtons of the same cal but no it didnt like them or my 120 load which again worked well in the others the only difference is the barrel contor the other 3 where all BDL'S and had a thicker barrel . Ill sort it but was just wondering as it seems to be a thing that people suggest to sort remingtons out .

A couple of spots an inch inside from where the bullets let go of the barrel. As already said, leave them if the rifle shoots good. Lead lapping is for shot-out pitted milsurps ... in a desperate attempt to get them back to shooting within 4-5MOA -- assuming they ever did.

There were some Remington 700's that came out a few years ago with barrel problems, tooling marks in the bore, off-centre chambers, etc. All classic examples of poor workmanship because of the "pay peanuts and get monkeys" fiscal management, and the reason Remington are gone as gunmakers. Nothing stuffs a business faster than a non-productive and over-paid management that attempts to rescue a failing enterprise by underpaying the staff who actually produce the goods!
Lapping with not correct the problem. Shortening the barrel back past the marks will work but at the cost of ballistic performance. Rebarrelling is the best choice.

I would be triple checking every other variable first off.....and definately try some other factory rounds...maybe federal blue box stuff just for shits n giggles...you MIGHT find it shoots better,if it doesnt well you what?$50?? worse off....
if it does,you then KNOW somewhere to start looking into...or just use that stuff LOL
have you managed to get anything to shoot well in this rifle????
have you taken it apart and looked for the obvious ????

Is the action bedded with the barrel channel clear and free floated ?

With regard to lapping, ShooterNZ is on the money.

I’ve had two Remington mountain rifles in 7mm-08 and .280R. Both needed to be bedded and free floated to get them to shoot. They were both fussy eaters. They both needed extra care and focus on shooting technique to get good 3 shot groups. 30mm @100 meter defined good.

I seem to recall many years ago that the Remington internal cost to produce a 700 barrel was something like $16...