LMT barrel break in?

[trout_champ]

So in my new LMT there were no instructions about barrel break in. When I emailed them this is what they said:

Randy

The upper you received was function fired and accuracy tested before it left the factory. No addition barrel break in procedures should be required.

Best regards,

Ryan Johnson
Sales Representative
Lewis Machine & Tool Co.
1305 West 11th Street
Milan, IL 61264
Phone: 309.732.9527
Fax: 309.787.2636

Do you guys still think I need to follow break in procedures? This is my first AR and I don’t wanna screw it up.

Thanks
Randy

[rboyes]

I've never felt as though anything special for 'break-in' was required. Just grab some ammo, go shoot, and have fun.

[SA Friday]

Question asked, and answered.

barrel break-in is a myth. go fire that smoke pole.

[Fromk]

It's not a myth but it's not required for every barrel. The JP match barrels, for instance, have a very specific procedure to fill in the little imperfections. I think it's related to the tolerances and purpose. Might be how the barrel is (or isn't) treated.

[mcantar18c]

I've heard two schools of thought on this, both from various "experts" (gunsmiths, builders, etc.), and I don't really know which one is true...

1. Barrels do not need a break in. The rifling is cleaned up at the factory as part of the standard manufacturing process and they come ready to spray as is.
2. The lands and grooves have some burrs that need to be worn away before you can see the full accuracy potential of your gun, and so you need to break it in to wear down those burrs.

#2 makes more sense to me, but I've heard both from reputable sources so I don't know what to believe.

[BPTactical]

A lot depends on the material and manufacturing processes used. Your LMT has a chrome lined barrel. No break in is required with a chrome bore.
Now on unplated barrels some break in is usually a good idea. Every barrel making process outside of hammer forging requires a cutting process for the rifling. During any cutting process you will have some burrs and irregularities present and the break in process involves burnishing those burrs and irregularities to a smooth, uniform bore surface. The bore surface also "work hardens" with use which is part of the break in as well.
Stainless steel usually requires a bit more attention during break in because it does not machine as cleanly as carbon steel, it tends to tear a bit rather than shear cleanly during machining operations.
There are a gazillion different schools of thought on break in of a barrel and I don't think anybody has "the perfect solution".

I like to keep the bore swabbed down between shots for the first 20 or so shots with a patch and bore cleaner with no copper remover in it(no bore brush). I want some copper to build up a touch but want to remove the powder residue and carbon between shots, I don't want to grind that stuff into a fresh bore.

[SA Friday]

Well, as you can see, it's a polarizing topic. I respect BPs opinion and we tend to agree on most things, but this we do not. This is probably the best thread I've read on the topic. http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1562996&page=1
Read the whole thread and Gale McMillan's opinion on the matter. I lean towards Lowlight's posts and the opinion of the gunsmith from Tac Ops in the thread.

I doubt anyone would contest that there rough machining in most new factory barrels. I think it's just what to do about it that people start to differ.

[Storm]

A lot depends on the material and manufacturing processes used. Your LMT has a chrome lined barrel. No break in is required with a chrome bore.
Now on unplated barrels some break in is usually a good idea.

<snipped>


Actually, LMT does make stainless steel barrels for the MRP (see here (http://www.lewismachine.net/product.php?p=147&cid=5)).

[BPTactical]

Actually, LMT does make stainless steel barrels for the MRP (see here (http://www.lewismachine.net/product.php?p=147&cid=5)).

Good save- Thanks
Good read SAFriday