When to change a barrel?

[Submariner]

Now that we have "busted" the chrome bore/reliability "myth", how about a more practical question: when does one change a barrel?

Too late did I learn to have a book to keep track of rounds fired on carbines. The barrel in question has no less than 7,000 rounds on it (one Awerbuck 3-day, 4 3-day classes with Pat, and workups for each class), probably more. We can shoot 100 yards here but seldom shoot outside 25 yards. So, degredation is accuracy at longer ranges is unknown.

Is there a good rule of thumb on when to replace the barrel?

[bigbore]

As long as you can still hit grapefruit at 100yds, you have a good carbine barrel as the throat burns.

If beat the crap out of the muzzle cleaning it, your barrel will be toast and have no short range accuracy much sooner.

[Griz]

You use a set of headspace guages to determine when the barrel is no longer safe.

http://www.bushmaster.com/shopping/gunsmith/hg0223g.asp

Or you just ditch the barrel when it's no longer accurate enough for your application.

[SethB]

I like chrome because I don't clean my guns. That said, velocity could degrade before accuracy, according to the CQB-R PP that is floating around. They lost 300 feet per second, but were still accurate enough for the kind of work I practice (25M and less).

[Harv]

From Griz

Or you just ditch the barrel when it's no longer accurate enough for your application


From SethB

I like chrome because I don't clean my guns.

Pretty much sums it up for me. I have a Bushmaster HBAR 16: barrel with 14K on it that was still shooting nice tight 1" grups at 50 yds with Surplus Federal/Guat and ADCOM ammo (and Wold too..:eek: )

I don't clean my barrels that often, just run a wet patch thru now and again. When Accuracy starts to go for your application... swap it out.

You know me Paul.... I hate every Nickel cause it ain't a dime....;)

[Submariner]

You know me Paul.... I hate every Nickel cause it ain't a dime....;)

So true. Hey, thanks for the .45 cal GI rod and chamber brush idea. My lowers have been multiplying and I don't want to buy cleaning rods for each one. :D

It looks like it's gonna be a long time before I have to buy a new barrel from Grant.

ETA: My wife loved that line about nickles and dimes.:D

[C4IGrant]

I would think that you would get 20K out of a chrome lined barrel. Hell, I know of 10.5 Noveske SS barrels that have over 15K through them and still shoot 1MOA!



C4

[Submariner]

I would think that you would get 20K out of a chrome lined barrel. Hell, I know of 10.5 Noveske SS barrels that have over 15K through them and still shoot 1MOA!

C4

Let's see: 12,000 rounds at $.25/round (yeah, right). Hmm. I'll be callin' ya in about $3,000.00. Gulp!:rolleyes:

[Nitrox]

You use a set of headspace guages to determine when the barrel is no longer safe.

http://www.bushmaster.com/shopping/gunsmith/hg0223g.asp

Or you just ditch the barrel when it's no longer accurate enough for your application.

HS probably won't change for 25K rounds (if ever) but free bore sure will. A throat measurement would be a good thing to have.

[Rob96]

Denny Hansen reports he got 80,000 rounds through his Oly Arms chrome moly barrel that was unlined before it developed reliability problems. I believe it was Denny over at the other board that posted pictures of 4140 DPMS barrels that 20,000 rounds full auto before failure.

[KYPD]

I would think that you would get 20K out of a chrome lined barrel. Hell, I know of 10.5 Noveske SS barrels that have over 15K through them and still shoot 1MOA!



C4
Hi. I am new to the forum, and have been lurking for some weeks. I am new to the AR-15 game, but have been shooting precision rifles for many years.

I would agree with Grant. I recall a military study (I hate to paraphrase without having a link to the evidence, but please forgive me) that showed that adequate (milspec) accuracy was consistently achieveable up to 30k rounds. Of course, better quality barrels give better accuracy longer, especially if properly maintained.

From exprience I know that, where accuracy is measured in 1/10", depending on the caliber, powder used (ball vs stick), and pressure of the load, 1,200 to 1,700 rounds is more often than not the limit of consistent accuracy, and one must needs replace the barrel to remain competitive after that.

In no case would an eroded barrel be unsafe, simply because it was eroded. For example, improper headspacing resulting from a replacement bolt, or lugs worn out over time, or lugs setback by excess pressure may lead to dangerous headspace problems, but not simply barrel erosion.

KYPD

[M4arc]

I would think 7K would be a little early to change out a barrel. I have two carbines with more than that down the pipe and I have no immediate plans to replace the barrels.

Keep shooting.

[VA_Dinger]

I would have to agree with M4arc.

I would not lose any sleep over a barrel until it hits at least 25,000 rounds. Even then it would only get inspected.

[Mig]

Change the barrel when accuracy becomes unacceptable to you regardless of the round count.