Im not a big believer in barrel breal in procedures, but JP seems adamant and I can't argue with the results I see online. Anyone here ever not break in a JP barrel? What were your experiences? I'm just very hesitant to put any sort of lapping compound regardless how fine or "non embedding" it is down a new $500 barrel.

No experience with JP but I would never use any lapping compound.

Clean, shoot, clean.
Shoot, shoot, clean
Shoot, shoot, shoot, clean.

You know that drill that works just fine.

Ran a bore brush through mine. Fired a couple of magazines out of it, sighted in attached optic.

Broke in.


5K rounds or so and still a sub-moa barrel.

I broke in both of my JP barrels but not according to JP's directions.  I am reticent to run any lapping compound through my bores, just don't feel great about it.  Anyhow, I kept it simple: shoot one, scrub out copper.  Did that for 5 shots.  Then, did a 5 shot string and scrubbed the copper out.  I did that for three 5 shot strings.  The total rounds equaled 20 (1x5 + 3x5 = 20).  

Not only are these the most accurate AR barrels I have witnessed, but when I believe it is time to do a copper scrub, I get close to nothing in terms of copper residue on my patches.  

They have to be some of the best AR barrels available to us.

What you did is very similar to what Lilja recommends.  I followed their procedure with one of their barrels recently.  Those barrels come hand-lapped from Lilja.  The break in is a bit tedious, but I believe it is beneficial if you are shooting match ammo.  The main thing they do is (1) they remove all or most of the tool marks from the throat, and (2) they do make cleaning, especially copper removal, much easier later.

I can't say that it necessarily helps accuracy, but theoretically it should.  I can say that it does not hurt.

Lilja's break in:

"For an effective break-in the barrel should be cleaned after every shot for the first 10-12 rounds or until copper fouling stops. Our procedure is to push a cotton patch that is wet with solvent through the barrel. This will remove much of the powder fouling and wet the inside of the barrel with solvent. Next, wet a bronze brush (not a nylon brush) with solvent and stroke the barrel 5-10 times. Follow this by another wet patch and then one dry patch. Now soak the barrel with a strong copper removing solvent until all of the blue mess is removed from the barrel. The copper fouling will be heavy for a few rounds and then taper off quickly in just one or two shots. Once it has stopped or diminished significantly it is time to start shooting 5 shot groups, cleaning after each one. After 25-30 rounds clean at a normal interval of 10-25 rounds. Your barrel is now broken-in."

Yeah man, not certain it helps with accuracy, but I did watch that video posted on the Hide several months ago with the guys from Bartlein.  They said the same thing, break ins help get tooling chatter in the throat smoothed out.  I also know Gail McMillan somewhat thought barrel break in was horseshit.  If someone wants to sport me a few test barrels, I'd be more than happy to do some testing, but I certainly don't care enough to do that on my dime.  

I respect the hell out of JP and if he recommends a break in with his barrels, the barrels will be broke in.

http://www.ar15.com/forums/t_16_4/4186_AR_15_Barrel_Break_In.html

I have a JP barrel and normally i dont do barrel break in, but this was my first precision built/barrel and when I saw JP recommended a specific way to break it in, i went and did it.  did it matter or not...idk.  but the groups i get from it are pretty amazing.

^This.

I laugh at the idiots who believe the "barrel break-in" myth.

I guess it's difficult to say one way or the other.  Do I like doing it?  Hell no, I hate wasting barrel life.  However, I also take the opportunity when breaking in a barrel to go ahead and zero my optics so that it is not a complete waste.  

Would Served_USMC's groups be better if he did a break in?  Does he even care?  Most folks don't. What I do know, is that the process cannot hurt the rifle (unless you fuck it up, of course), and if it has the potential to smooth out tooling chatter in the chamber and have other positive effects that we may not have any clue about, why wouldn't you do it?  It's 20 rounds and about an hour of your time.

As I stated before, if the heads at Bartlein and JP say it is a good process to do, I'd take their advice over the internet no-names, but that's me...kind of into that authoritative sourcing "thing."

Has anyone actually know of, or have done a bore scope comparison on technique...or lack of, to determine if there's any validity to any of this?

When I had JP's I did the same and had the same results.

You're going to need more than a borescope to verify whether barrel break ins are valid, but I suppose it would be a start.

I always follow the manufacturers recommendation.

I recently installed a Lilja 20" barrel in .308 for a friend's MEGAlitihic AR10.

We did barrel break-in according to Dan's instructions, and used that ammo/opportunity to sight in the scope, and practice taking good aimed shots.  So it wasn't really a waste of time.

I learned some things and have to say I am a convert.


The procedure was 1-shot then clean for the first 10 rounds, then 5 shots and clean until you hit 30 rounds.

Cleaning procedure was using a bore guide and coated dewey rod, wet patch with Butches, 10 strokes with a bronze brush, dry patches x2, wet patch with Sweets X2, 5 minute wait, wet patch with Butches, Dry patch.

Observations:

The amount or carbon fouling in the barrel was consistent for every shot.
The amount of blue on the second sweets patch was significant at first, and gradually tapered off until the 6th or 7th patch, then became really light.  You could really see the barrel smoothing out and not taking on so much copper fouling.  By the last 5 shot group, it was undetectable.

That barrel is a TACK driver.  Really impressive and WAY better than many other "1MOA guaranteed" barrels I have used, that never held that claim.

I did. It was first AR build. and first precision type barrel
JP told me to do it
So I did it. Took a while and wasted 120 rounds of wolf gold. JB Polishing compound. Hoppe and a lot of patches
Dont know if it made a difference. But it does shoot better then I ever could!!

I'm one of those people.  I've had my JP CTR-02 rifle for about 2.500 rounds and after I got it brand new, I just started shooting and cleaning after about 300 rounds and there has been zero degradation in the rifle's amazing accuracy.  

This year, as an experiment, I stopped cleaning the barrel altogether to see at what point accuracy will drop off.  Usually, the rifle is used at 600 yard matches and at the 800 yard line for fun, but I frequently fire 100 yard test groups and they're as tight as ever.  I'll clean the bore when I notice any deterioration in accuracy.  It's been about 600 rounds since I started the no-clean test of the bore.  I still clean the BCG, lower, and the upper, just not the bore.

The only thing I've noticed so far, is that as the barrel ages, I'm getting more velocity.  It's gained about 50 fps since new and I revise my ballistic tables about once per year.

With my pet loads, I find right around 450 rounds (maybe 475) my groups start to open up.