Barrel Life

[Phil Giordano]

Barrel life means different things to different people. While a 1/8" loss of accuracy at 100 yards would be shot out to a target shooter, the average hunter would probably never notice. So how many rounds to "shoot out a barrel" can vary depending upon who you're asking. I've had a couple varmint rifles start showing a slight loss in accuracy, so to me they were shot out.

I agree with the others about improper cleaning and how the guns are shot makes a huge difference. The late Warren Page said that barrels are actually burnt out, so letting them heat up makes a big difference in barrel life.

That's a good point, how much a barrel is considered "shotout" can be a very subjective...
Also add that the more you shot it, the more proficient you become, so...maybe at some point there is a sort of compensation - at least in hot hunting rifles/calibers, I mean...

 

[Bob Nelson 35Whelen]

I was reading about the early testing of the Army’s M24 sniper rifle when I ran across this:

“The actual rifle requirements for accuracy were .35 MOA from a machine rest and according to Major John Mende (ret.) this accuracy had to be maintained to 10,000 rounds. He stated, “Interesting side note was there was a 10,000 round requirement for the barrel to maintain the original accuracy. In fact after some 10,000 round tests we discovered the accuracy improved. A few barrels were tested past 20,000 and accuracy never went below the original accuracy requirement.”

Shortly after reading this article, I read some random articles on barrel life and the conclusions were all over the place. Some guys state a 6.5 Creedmoor barrel shoots-out at 1200 rounds and then some guys state that for calibers like the 6.5 or 308, 5000 rounds is more realistic.

Personally, I have never shot any of my guns enough to shoot a barrel out.
So, any thoughts or experiences would be appreciated.

@Randy Bo
I'm not saying it is wrong but in my experience I have had a 22/250 barrel loose its accuracy after 2,500 shots. Kangaroo shooters regularly shoot barrels out here in Australia after roughly 8,000 to 10,000 rounds of 222 rem and 223 so seems a bit pie in the Sky even with a chrome bore.
Bob

 

[Bob Nelson 35Whelen]

To me, barrel life depends more on "how" you shot than "how many". If you take time between groups, let cool the barrel well, and clean deeply the barrel every 30/40 shots, a barrel can really last for very long I guess. Also a good break in seems to prolong barrel life. A factor that "burns" the barrel quickly is the type of powder, a very slow powder in fact (producing more heat) seems to erode the rifling faster than a quick one. Me, I have shot a lot with a 300 Winch and a 300 Wby and I yet have to see any effect on groups - I believe "cooling" & "cleaning" are key factors, more than numbers of rounds.

@Phil Giordano
I have never run a barrel in in my life and only clean when accuracy starts to go off. Anything up to 2 to 400 rounds depending on the rifle. I haven't noticed a difference in barrel life doing it my way to yours.
More rifle barrels are ruined by IMPROPER cleaning than shot out thru throat erosion.
Bob.

 

[Inline6]

I was reading about the early testing of the Army’s M24 sniper rifle when I ran across this:

“The actual rifle requirements for accuracy were .35 MOA from a machine rest and according to Major John Mende (ret.) this accuracy had to be maintained to 10,000 rounds. He stated, “Interesting side note was there was a 10,000 round requirement for the barrel to maintain the original accuracy. In fact after some 10,000 round tests we discovered the accuracy improved. A few barrels were tested past 20,000 and accuracy never went below the original accuracy requirement.”

Shortly after reading this article, I read some random articles on barrel life and the conclusions were all over the place. Some guys state a 6.5 Creedmoor barrel shoots-out at 1200 rounds and then some guys state that for calibers like the 6.5 or 308, 5000 rounds is more realistic.

Personally, I have never shot any of my guns enough to shoot a barrel out.
So, any thoughts or experiences would be appreciated.

Rate of fire has a lot to do with it too. Shooting PRS style matches I have had to fire strings up to 20 rounds in 90sec. Most stages are 10rds in 90sec.

Personally
1- 6.5CM lasted 1900rds
5 - 6CM last between 900 to 1200 rds
4 - 6XC lasted between 1400 to 1800 rds
1 - 338LM lasted 1100 rds

I don't shoot like I did, have shot 308 just have not burned one out yet. When shooting field style comps you need every advantage you can get. That's the reasons for the 6mm.

Read what @lockingblock is writing, a lot of truth in what he has written.

 

[lockingblock]

PRS and similar disciplines can have their own challenges. Long, heavy bullets can wear faster as there is more bore contact.

Barrels used in sandy places wear faster.

Barrels fired with any moisture in the bore…or oil can be damaged due to the incompressible nature of liquids and resulting dents in the bore.

Hard bullets eat up throats…military 855A1 being a prime example.

Powders can burn at hotter temps. Old Cordite was super bad.

Rust kills metal. Carbon steel rusts if not cleaned and oiled.

Cleaning kills barrels when done wrong.

Carbon is a bigger enemy than copper.


Clean gently. Never put solvent anywhere that you can’t remove it from. Use gentle solvents like Hoppes #9. Avoid Sweets and similar ammonia based products unless you must remove copper and then use for a very short time, removing it completely and oil when done. Brass core bronze brushes. Brass tools only for anything going down the bore. Carbon fiber rods and bore guides…no oil or solvent in the trigger. Finish with a light oil in the bore to put in storage.

If the trigger is oily or gunked up, pull the barreled action and flush it with lighter fluid. Lighter fluid will get a trigger working that’s gummed up.

 

[Lone Star Bluegrass]

Like some others have written, cartridge and load has a significant vote. The .264 Win Mag mafia are usually lucky to get 2k rounds of life—lotta powder burning down a tiny hole.
Another variable is the type of shooting. If everything you do is slow fire, a couple of shots at a time you’ll get more life than if you’re burning through the same volume only in rapid fire increments.
Competition ARs in .223 usually go out by 3-4k rounds, almost always in throat wear (look for case head separation as a warning sign). With melonite coating this life can be extended by 2-3x.
M24 was alright for the role it served—an accurate rifle that was easy to shoot and easy to train a soldier to shoot better than the average bear. It’s not a match rifle though.

 

[SLG]

I had an M24 issued at one point and have shot others. As mentioned earlier, I don't think they could consistently shoot .5moa, let alone .35 for 10,000 rds. Mine was usually .75 or better, but could certainly be worse depending on how I held my jaw. 118LR was definitely a factor as well.

I consider 308 to have around a 5,000 rd match life, that is to say, capable of its top accuracy. They will usually go 10-12,000 rds if you are willing to accept sub moa ability. Todd Hodnett, one of my early long range instructors, told me that many of his Larue gas guns would go 20,000 rds with acceptable accuracy. That seems like a lot to me, but Todd knows what he is doing. I had a Larue missed at one point as well, and I will say that it was a hell of a gun.

I have worn out many 14.5" 5.56 barrels. They went to right around 20,000 rds each before giving up the ghost. Again as mentioned before, what level of accuracy you are willing to accept and how you treat the gun matters. I never babied them or even cleaned the bore much, but I also limited full-auto fire to almost zero. I did shoot them hot and fast though, and it took me 1 year to reach that burnout point each time.

 

[40inarow]

I had an M24 issued at one point and have shot others. As mentioned earlier, I don't think they could consistently shoot .5moa, let alone .35 for 10,000 rds. Mine was usually .75 or better, but could certainly be worse depending on how I held my jaw. 118LR was definitely a factor as well.

I consider 308 to have around a 5,000 rd match life, that is to say, capable of its top accuracy. They will usually go 10-12,000 rds if you are willing to accept sub moa ability. Todd Hodnett, one of my early long range instructors, told me that many of his Larue gas guns would go 20,000 rds with acceptable accuracy. That seems like a lot to me, but Todd knows what he is doing. I had a Larue missed at one point as well, and I will say that it was a hell of a gun.

I have worn out many 14.5" 5.56 barrels. They went to right around 20,000 rds each before giving up the ghost. Again as mentioned before, what level of accuracy you are willing to accept and how you treat the gun matters. I never babied them or even cleaned the bore much, but I also limited full-auto fire to almost zero. I did shoot them hot and fast though, and it took me 1 year to reach that burnout point each time.

All of you guys are right. Huge cartridges with small diameter bullets have high flame temperatures which burn up chambers. If you want high accuracy life, which in my case as a Silhouette Shooter, is defined as 1" groups on demand at 200 meters, than when a barrel is shot out it goes to 4" the way to do it was established long ago, at least in the 1990s. Using moly coated bullets, and JB Paste and Kroil cleaning will maintain a high accuracy level for an extended number of rounds. Also, a well balanced cartridge.

I have not found moly coating to have any effect on larger size cartridges like my 338 Win. But I don't put 5000 rounds through it.

I read our Swedish friend say cleaning has no effect. Given the accuracy standard they wish to achieve, I guess you could say he is right, but that statement is patently incorrect because none of us would be happy with that standard.

I realize we are hunters here on this forum and the accuracy and longevity requirements are far removed from benchrest/silhouete/high power shooters, but the knowledge accrued from those disciplines are valuable to the shooting world in general.