Worn centerfire barrels, how did it show itself?

[His lordship.]

As many of the members here have lengthy experience with centerfire rifles, have you ever worn out a barrel, and how did it show itself? 

Rick Jamison mentioned a worn barrel in his book that would have one shot out of five that would fall short.  He could see the bullet hit the dirt short of the target, and he checked the bore further to see that the throat had extensive erosion.

I have also heard of some big game rifles, I think .458 was mentioned, or at least it was in that family of calibers, that would only last 500 rounds before the barrel had to be replaced!  Seems rather extreme to me.  I have also heard of people shooting their SKS's up to 20,000 rounds without any problems.  The military at Camp Perry used to rebarrel their 03' Springfields every year, don't know if they really needed it, or was done to keep them in peak shape.  How long do barrels in say...a 30-06, last if the rate of fire is kept down to 5 or 10 shot groups and allowed to cool before the next 5-10 shots?

Thanks.

[kyelkhunter3006]

For most normal calibers, you should get 3000-5000 rounds out of the barrel.  A .308 would be close to 5000 rounds or more, a hot loaded .243 would probably show serious erosion after 2000 rounds.  It all has to do with velocity, expansion ratio of the bore vs powder charge, etc.  The baseline is that the faster the bullet, the faster the barrel will wear out.  The hot varmint calibers and big overbore magnum's are hell on barrels.  You should get several thousand rounds out of a 30-06 with no issues.

[wncchester]

The .458 Win. will last for thousands of rounds.  If anyone wanted to shoot it that much!

[Slamfire]

My .243 started scatterin' 80 grain loads over larger and larger areas, while it could still put 100 grain loads in small spaces. I'd had the gun a good 25 years and figured it was time for a change. Had it rebored to a 6.5 mm wildcat called the .263 Express, nowadays Remington calls the same chamberin' the .260.  Dumb Luck, as my favorite Uncle used to say, when things go right without apparent effort. 

[jro45]

I have shot out a couple and the way they showed me was that I couldn't get a tight group. The bullets seemed to go all over the place using the same load I have always used for tight groups.

[beemanbeme]

I can't imagine how an eroded throat would cause one bullet out of five to come up short of the target but maybe it was a slow news day and the deadline was looming. 

My experience has been that the groups start getting looser. Maybe with an occassional unexplained flyer.  An adjustment of COL and powder can sometimes correct things for a while.  Of course, if your rifle is limited by the magazine box, that's not an option. In that case, setting the barrel back a thread or two and rechambering wil work. Sometimes that'll cost you as much as a new barrel.  I had a 22-250 that I used for Pdog shoots and some "friendly" target matches. Every spring, I would adjust the cartridge length to compensate for the last years throat erosion, and then, I'd shoot it acrost my Chrony and add a pinch or two of powder to bring the velocity back up.  When I finally sent it off to be rebarreled, I doubt that .25" of the bullet was seated in the neck of the cartridge.  But then, I fired the rifle only single fire.  How many rounds had gone thru the barrel?  I don't know as I don't keep those sort of records but I had the rifle for several years and went on at least one Pdog shoot a year where I would shoot upwards of 1000 rounds.

[Catfish]

Chris,
   I would recomand that you forget what you read. 1st. off, the .458 Win. mag. is far from a barrel burner. Barrel burners are small cals. with very large cases, sometimes called over bores. The throught wear in these rounds comes from the burnning grains of powder that are being forced into the throught of the barrel, they act like a blow tourch. When you fire a barrel burner at a high rate of fire and get the barrel hot you greatly increase the rate at ehich you burn out the throught. Rounds with straight wall cases or nearly straight wall cases don`t burn throughts like the cases that funnel down a large volume case to a small hole. As a through begin to wear you can seat your bullet out longer and maintain the accuracy untill you reach the point were your bullets are to short to set out any more.
   As for 1 out of 5 bullets falling short being caused by a shot out barrel I doubt. The loss is in accuracy and not in velosity. What happens is the barrel no longer puts enough spin on the bullet to stablize it. MY GUESS as to why is that as you burn out the through the jump the bullet make befor it get to the lands gets farther so the bullet is moveing faster as it hits the lands, and it is not spinning, so as it hit the lands and starts to spin it will slip in the lands and deform the jacket of the bullet.

[safetysheriff]

try reading this article that tells what Boots Obermeyer, premier rifle-barrel mfr' and shooter has to say about barrel wear.........for chrome-moly high-carbon barrels, and those made of stainless steel.

very interesting!    he talks about small particles of metal being broken/chipped off the barrels surface and causing flyers.    i guess his use of a bore scope would be a big part of his experience with figuring out some of these things.   

     www.snipersparadise.com/tsmag/june2001.htm   

Boots tells us, after many years of experience, that heavy bullets and large doses of slower powders make for barrel erosion.   BUT, the .243 can eat a barrel when shot in competition at the rate they sometimes have to fire........ in less than 1800 rounds! 

take care,

ss'   

[mikedb]

For most normal calibers, you should get 3000-5000 rounds out of the barrel.  A .308 would be close to 5000 rounds or more, a hot loaded .243 would probably show serious erosion after 2000 rounds.  It all has to do with velocity, expansion ratio of the bore vs powder charge, etc.  The baseline is that the faster the bullet, the faster the barrel will wear out.  The hot varmint calibers and big overbore magnum's are hell on barrels.  You should get several thousand rounds out of a 30-06 with no issues.

This is right on.  It compares almost exactly to a table I have from somewhere that gives barrel life vs. caliber and powder used.

[454Puma]

I expect all my rifles will be worn out by my Grand children! Meaning with care and maintenace you will never wear one out! Unless you shoot 2-3 thousand rounds a year for 10 years! Just stay away from those ultra(Mags) velocity rounds!

[jro45]

I beleave if you let your barrel cool after 2 or 3 shots and clean it good it will last a long time. The ones I shot out were fired over 3000 times acouple had cheaper barrels on them and didn't make to 3000 rounds. I only use Shilin barrels any more.