Barrel Break-In

PSA Products AR-15
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I have 4 parts kits from PSA. All 4 were nitrided barrels.

I’ve read some belive the barrel break-in is not necessary due to the current manufacturing process. Specifically stainless steel barrels being discussed.

  • stop here if you follow the no bresk-in required belief.

Supplies
Lube (your preferred lubricant for firearms)
30 rounds
Bore snake
Chamber brush on cleaning rod, to clean the barrel locking lugs and chamber.
Toothbrush (I keep an otis nylon brush in my range box.)

Process:
Fire 1 round.
Run a lubed bore snake in your caliber through the barrel.
Lube chamber brush lightly and run it, 4-5 turns in the chsmber.

-repeat above steps 4 time for a total of 5 rounds fired.

Now move to 5 shot groups.
This is where I start to zero the gun.
Fire 5, then bore snake and chamber brush as above.

  • repeat 4 times for 5 × 5 shot groups with bore snake and chamber brush.

Barrel break-in is complete. Iron sights or optic are now zeroed or very close to zero. 25m target zero, confirm at 100m (fine tune as needed). Or do your preferred zero for your guns.

If you zeroed your iron sights now zero your optic. If you only run iron sights or an optic your completed on this task.

You may meed to confirm zero with elevation change and teperature change, this is more critical shooting over 200yards/200m. Teperature change = air density change so ever 6 months winter to summer. Your point of impact can change.
Elevation change = air density change. +/- 1,500 feet, confirm zero as needed.

Example: my .308 bolt gun at sea level hits destabilisation velocity at 800-825 yards. At my elevation of 5,600 feet my rounds hit destabilization velocity at 995-1015 yards.

My .308 bolt gun was picked up used, I did no barrel break-in. I did clean the barrel, chamber and bolt assemby prior to 100 yard zero with factory load selection. Once factory load was chosen (sub-moa accuracy was my decidingfactor) I zeroed my optic.

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I have done this with all of my AR-15 rifles except one. That one (non-psa) is the only one I have issues with.

Issue being spent cartridges sticking in the chamber. The rim of the case gets ripped of by the extractor and I need to punch the case out of the chamber with a cleaning rod. I have changed extractors and the issue persists. From discussion with my gunsmith chamber reamer or rebarrel the firearm as we suspect a tight, out of spec chamber.
He ordered go no-go gagues but we’ve not gotten the same days off to test.

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i think there is something to be said about break ins, and how well the actually work. but to each their own.

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My .02 cents on break ins. I continue running wet/dry patches between each shot until the shot group at 50yds settles down.

Some rifles have taken me 25 shots; long morning when letting the barrel stay cool.

Then a wet/dry patch after each 10 rnds until a 100 yds zero is confirmed.

I’ve seen quite a few ppl bring out new rifles and start mag dumping…

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Thanks, @AZ_Joe , I like the simplicity of your break-in. I tried it today using 40 rnds on a new rifle (it has been sitting for a few months waiting on me). I’m thinking the 6.5 Grendel 18" SS barrel could use another 40 to 60 rnds for break-in compared to a nitrided one - curious about your thought on that…

I bought that upper on a whim. Not sure why other than I’ve always wanted one. With good ammo it probably costs more to shoot than .308, but Wolf 100gr isn’t at a bad price right now.

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My understanding and if anyone else has better knoledge I hope they speak up.
Note*
I thought this was just buch of rifle mysticism. Now it seems to mesh with accuracy fairly well.

Barrel break in is mechanically using the projectile to lap any machining burs (aka polish the rifling). The method I posted was explained to me by a former military service buddy. He got injured in combat, as a low impact option during recovery he was sent through armores school for his unit. He was working as a gunsmith with my FFL when we met.

This was used more with a chrome lined M4 during his active duty.

From a machining standpoint stainless and nitried barrels are less of an issue. The chrome lining builds up on any imperfections in machining the barrel, creating extra drag at odd spots as the projectile gets set free. That drag can slow or alter the effect of the rifling being imparted on the projectile. Higher round counts on chrome lined barrels would be logical.

Additionally, every barrel is different (my own research). In theory, 5 rifles off the same production line are all very likely to have a different load that shoots best from each. Were talking fractions of MOA difference.

Also, AR pattern rifles have some parts like the bolt lugs to the barrel lugs that need some wear in for the parts to consistently mate. This is basically the cartrige in the chamber being, shot to shot more cosistent in its orientation to the rifling.

With all that said, your rifle may need more break in. Excluding things like a production lot change in ammo, the group will settle down at range once the barrel is broken in. Im not recalling exactly what that is but, may be at 300 to 500 yards for 6.5.

I am not very knowledgeable on 6.5. So that range for consistency may be way off. I’m faily sure I’ve had a cold or a nap since learning some of this and likekly forgetting much. :rofl:

I want to say 127 gr is a better load for 1,000 yard accuracy but again I’m not recalling what I picked up for people arriving from out of state for a 1,000 yard course 3-4 years back. Might have been 137 grain load ?

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I just relized I made an error in my original description.

No bore snake was used in how I was taught this.

Cleaning rod, bore brush and patch jag or sloted patch holder were taught.

I run my bore snakes through the wash. They get so much gunk and debris in them its like running an emery cloth down your barrel. Not good for barrel longevity or accuracy.

I started using the bore snake (freshly cleaned) as I only keep one cleaning rod in my rage gear. Changing from the bore attachments to the chamber brush and back made this a very labourious effort. My buddy made a chamber brush handle to keep in hisrange box he has done this so often.

2 of my rifles got the mdified version with bore snake. Ive not noticed any accuracy issues vs the cleaning rod only method.

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Whew! Bore snake for me. I suppose I better find my cleaning rod to continue the process, but the bore snake seems a lot easier. The cleaning rod is supposed to last much longer since the snakes wear out.

Interesting information from your military friend; it sounds perfectly locigal that the chrome lining would build up on imperfections. Competition shooters seem to follow strict break-in protocol too.

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You’re not just breaking in the barrel, you’re also breaking in the bolt.

The circular machining marks on any freshly machined piece of metal can have some sharp edges.

Breaking those edges and essentially sanding them is part of firearm break in.

Of course the cost to demonstrate the usefulness of break-in can be rather high.

Just get some brass stuck in the chamber, and then try to get it out.

That was one thing I learned when discussing a new rifle with a local gun smith at a local firearms store.

They said they would only charge me if they were successful in getting the brass out.

They said it was the only piece of stuck brass that they haven’t been able to extract from a chamber.

But, besides stepping up loads in smaller increments, one thing I learned is to shoot est. 150 factory rounds through a rifle before trying a re-load, especially an aggressive re-load.

When all was said & done and they returned the rifle to me with the brass still stuck in the chamber, that was the one “Lesson Learned” that we sort of agreed on.

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Good stuff @LBL !

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All the uppers I have purchased from PSA have been test fired at the factory. Kind of negates the whole rub the rifling with petroleum distillates ritual.

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