Life of Barrels

[Old Trev-39]

Hi All,
Am looking for the following for barrels using the Win .284 cartridge.
(1) Rounds fired before going bad.
(2) Cut or Buttoned rifling.
(3) Standard or angled lands such as 5C or 5R.
My reason for asking is that I have had a cut angled lands barrel fail at around 1000 rounds. I have had 3 buttoned barrels go over the 2000 round count. As I am in the market for a new barrel, I want to know if others have had the same experience before I make a purchase.. Cleaning procedure is not the cause,as I have used the same ingredients and method for over 20 years with no problems.
Cheers,
Trevor.

[bruce moulds]

trev,
have used cut and buttoned square rifling, and cut canted lands in 284.
can't really tell any difference in barrel life.
about 2400 rounds will leave enough throat end rifling to get a rechamber.
flame erosion seems to be the factor of greatest metal removal, so rate of fire can be the deciding factor.
the 10 second delay on e.t. might save a bit of money.
bruce.

[Wal86]

Trevor,

When you say, your barrel has failed... In your observation what specifically has failed?

Cheers

[Old Trev-39]

Initially I was getting un-explained vertical shots. Chronographed loads over Labradar and had 45 f.p.s. spread. This is not a loading issue as the same loads in a different barrel produced a 4.575.inch group at 1000yd. in Townsville on Saturday. Before my post I slugged the barrel. After initial sizing of slug and about 2 inches down it moved with a little pressure and then no resistance for a couple of inches, and then firm for rest of barrel. Bore scope shows no apparent wear in this section that I can see.
Cheers,
Trevor.
P.S. The barrel had been thoroughly cleaned before slugging.

[Wal86]

Initially I was getting un-explained vertical shots. Chronographed loads over Labradar and had 45 f.p.s. spread. This is not a loading issue as the same loads in a different barrel produced a 4.575.inch group at 1000yd.

I think the problem is what works in one barrel doesnt always work in another barrel..

[KHGS]

Initially I was getting un-explained vertical shots. Chronographed loads over Labradar and had 45 f.p.s. spread. This is not a loading issue as the same loads in a different barrel produced a 4.575.inch group at 1000yd. in Townsville on Saturday. Before my post I slugged the barrel. After initial sizing of slug and about 2 inches down it moved with a little pressure and then no resistance for a couple of inches, and then firm for rest of barrel. Bore scope shows no apparent wear in this section that I can see.
Cheers,
Trevor.
P.S. The barrel had been thoroughly cleaned before slugging.

Classic symptoms of carbon fouling!!!!! I have rejuvenated many "worn out" barrels by removing carbon fouling.
Keith H.

[Old Trev-39]

Hi Keith,
Definitely not carbon fouling.
Wal86. What I meant was same components used and the same procedures that have I have used for years with no problems.
What I want is some numbers on how many shots before barrel has gone south, and type of rifling pattern. A S.A.U.M. barrel in Cairns went south at 600/700 shots.
Cheers,
Trevor.

[bruce moulds]

trev,
not having used a saum I have no idea what to expect from one, but a 6.5/284 could do that if shot rapidly.
I have had them go at 900 shots.
std 284 win is a much more forgiving cartridge.
the 6.5 version is rarely worth a rechamber on an economic basis, where the 284 can be, and that after more shots.
did you ever slug that barrel when it was new?
could you have used j.b. more in that area?
I will never forget the time I slugged a sprinter barrel.
tight and loose spots all the way along.
bruce.

[KHGS]

Hi Keith,
Definitely not carbon fouling.
Wal86. What I meant was same components used and the same procedures that have I have used for years with no problems.
What I want is some numbers on how many shots before barrel has gone south, and type of rifling pattern. A S.A.U.M. barrel in Cairns went south at 600/700 shots.
Cheers,
Trevor.

Trevor,
The most common causes for the demise of barrels early or otherwise are, 1) induced damage either to the crown or elsewhere in the bore, 2) severe throat erosion, 3) inclusions (dirty steel) or..............wait for it....... carbon fouling!! Many times carbon cannot be visually detected, but can be found with a lead slug. Fair wear & tear is always preceded with heavy fire cracking in the throat followed by erosion. Some barrels will "go off" soon after evidence of erosion, some will continue for quite awhile after.
I am not a big fan of "canted rifling" or "micro groove rifling" but see little difference in the wear rate that could be attributed to other forms of rifling. I have fitted (hundreds) & used both buttoned & cut rifled barrels over the years and I am satisfied that the method of rifling has little to do with wear rate.
SAUM barrel life seem to average from 1200 to 1800 rounds depending on the loads fired & the rate of fire. Short fat cartridges tend to yield a slightly shorter barrel life than longer slimmer cartridges of similar capacity. 40 degree shoulders and longer necks also tend to extend barrel life.
Some batches of powder will carbon foul more than other batches of the same powder. Carbon fouling may be worse in hot weather and with rapid fire. These are the opinions of this geriatric gunsmith for what they are worth.
Keith H.

[Old Trev-39]

Keith,
There is erosion so this could be the problem. There was erosion in the other barrels that that went longer. Maybe this one decided it had had enough.
Thanks for your input.
Bruce,
I am not a fan of J.B. and vary rarely use it. I still have my first pot I bought over 10 years ago. If barrel makers say not to use abrasive cleaners, that is good enough for me. I always slug a new barrel.
Cheers,
Trevor.

[KHGS]

Keith,
There is erosion so this could be the problem. There was erosion in the other barrels that that went longer. Maybe this one decided it had had enough.
Thanks for your input.
Bruce,
I am not a fan of J.B. and vary rarely use it. I still have my first pot I bought over 10 years ago. If barrel makers say not to use abrasive cleaners, that is good enough for me. I always slug a new barrel.
Cheers,
Trevor.

JB is a great product...........if used correctly which is why barrel manufacturers do not endorse it. If used as it should be it can be a barrel saver, but it can ruin barrels if used incorrectly. I am never without it, but use it infrequently.
Keith H.

[Frank Green]

I'll throw some things in the fire here....

I'm o.k. with JB Bore Compound but not the Bore Brite. The problem with the paste type cleaners (even the ones in the liquid form) is they get used improperly or to aggressively and or I feel they get left in the bore and not cleaned out properly and when this happens it can ruin the barrels.

The style of rifling either conventional or 5C or 5R has no bearing/impact on barrel life. The only exception to that I make is the ratchet style rifling. Those really thin knife edge lands don't hold up. There is no meat for the wear.

Button vs. cut rifling. On average the cut rifling does last longer. I've maintained that for years and years. This is due to the fact that during button rifling the button will work harden the bore. This isn't just me saying it either but ammo manufacturers, bullet makers using ammunition test barrels in controlled conditions have always told me the same thing. How much longer? At a min. 15%.

Can a button barrel last a long time? Sure it's just not the average. Can a cut or button barrel die prematurely? I will say yes. Can it be in the steel? I will say yes but I feel that is more rare than the norm.

Other things effect barrel life....as mentioned....rate of fire, and how it's being cleaned.

Not mentioned.....the type of powder being used (the double based powders are harder on barrels and will shorten barrel life...the trade off is you can get higher velocities but as the saying goes...it cost money to go fast), types of bullets effect barrel life. The heavier/longer bearing surface jacket of the bullets will shorten barrel life as well.

What the barrel is chambered in and type of chamber.....a .284win. is going to be much easier on the barrel vs. a 7 short mag. Also some cartridges like the .243win. with that short neck/shoulder angle burns the throat out faster as well.Guess what when we do barrel life testing at all....we chamber them up in .243win. because it's that hard on the throat. The ammunition makers also don't like the round as well. They have to load for a velocity and a given pressure and once that throat starts to get the wear the barrel might still shoot accuracy wise but the pressure will start to vary to much and effect velocity and when that happens they have to pull the barrel from service. It's not uncommon for them to pull the barrel at about 800-1000 rounds in .243win.

Sometimes guys think the barrel has prematurely died but as has been previously pointed out a good cleaning can bring it back and or damage to the crown and a retouch up on the crown can bring the barrel back as well. When the bullet leaves the barrel you get a gas cutting effect from the powder and it will wear the crown. That's why I don't like the crowns with a sharp edge on the muzzles bore.....we put a 60 degree chamfer on the bore edge. The style of crown, 11 degree, flat, stepped recess, sporter radius etc...to me makes no difference but the chamfer on the bore edge helps.

Later for now.....Frank

[KHGS]

I endorse Frank's points 100%, they mirror my findings over 40 years of full time gunsmithing!!! There are a high number of shooters who do not clean their barrels correctly, that is fact!! I will not use double based powders due to their barrel burning propensity!! As Frank says the danger with abrasive cleaners is that they are often not completely removed after using. ADI powders are generally easier on barrels than some other powders as they usually burn a little cooler. Hot loads however are your barrel's worst enemy no matter which powder is used.
I have stated before (I think on this site) that barrels go through three stages in their life and may need to have the cleaning regime altered during these changes in order to get the best from them over their life.
I have one barrel chambered in 280HI that has logged up just under 3000 rounds and still shoots as well as I can. This is a buttoned barrel, I still say that is does not matter how a barrel is made, but what matters is how well it is made and the quality of the steel.
The thing I see most in "problem" barrels is the incidence of "dirty steel" this will manifest itself in pits within the bore. These pits in themselves do not usually cause any problem, unless they occur around the crown.
Keith H

[Frank Green]

Well put Keith!

As I went thru out the day and thought about this some more and Keith hit it pretty good about how barrels seem to go thru stages. I always tell military snipers when I do classes and customers on the phone etc...you have to learn how to pay attention to the gun/barrel. It will tell you what is going on but you have to learn how to read it.

One of our allies shooting .338 Lapua sniper rifles with our barrels. The first couple of batches of barrels we made them are out of c.m. Steel. All later batches are s.s.

About a year ago one of the armorers had called and talked to me a bit on the phone about cleaning etc....at that time they had two barrels. One had 4K rounds on it and the other had around 5200 if memory serves me right. Anyways the snipers brought them they’re rifles saying they didn’t shoot anymore. The armorers felt they just needed a good cleaning. So they cleaned them properly. Keep in mind they are shooting box ammo. The barrels have lost a solid 200fps velocity wise but after a proper cleaning both barrels still shoot sub moa and again with box ammo. He said they just need to put a few more clicks on the scope. Are the barrels probably past they’re proper service life? I’ll say yes but it does go to show not necessarily junk.

I’ve got a .338 Lapua accuracy test barrel that was returned to me from Sierra after they retired it. That has 3,680 rounds on it. I milled a window into the side of the barrel to use as a training tool.

The last five barrels I got back from from another ammo/bullet maker in .308win. And used for accuracy testing. The barrels where retired when they would no longer hold .5moa. One barrel had just shy of 10k rounds, and another at 11,260, 13,240, 14k+ (which I had wire edm cut in half as a training tool) and another that was over 12k rounds.

Does this mean that every barrel should go x amount of rounds or should be used to that extent? The answer is no. Again though like I said pay attention to what the gun is telling you.

Later, Frank

[Rich4]

I'll throw some things in the fire here....

I'm o.k. with JB Bore Compound but not the Bore Brite. The problem with the paste type cleaners (even the ones in the liquid form) is they get used improperly or to aggressively and or I feel they get left in the bore and not cleaned out properly and when this happens it can ruin the barrels.

The style of rifling either conventional or 5C or 5R has no bearing/impact on barrel life. The only exception to that I make is the ratchet style rifling. Those really thin knife edge lands don't hold up. There is no meat for the wear.

Button vs. cut rifling. On average the cut rifling does last longer. I've maintained that for years and years. This is due to the fact that during button rifling the button will work harden the bore. This isn't just me saying it either but ammo manufacturers, bullet makers using ammunition test barrels in controlled conditions have always told me the same thing. How much longer? At a min. 15%.

Can a button barrel last a long time? Sure it's just not the average. Can a cut or button barrel die prematurely? I will say yes. Can it be in the steel? I will say yes but I feel that is more rare than the norm.

Other things effect barrel life....as mentioned....rate of fire, and how it's being cleaned.

Not mentioned.....the type of powder being used (the double based powders are harder on barrels and will shorten barrel life...the trade off is you can get higher velocities but as the saying goes...it cost money to go fast), types of bullets effect barrel life. The heavier/longer bearing surface jacket of the bullets will shorten barrel life as well.

What the barrel is chambered in and type of chamber.....a .284win. is going to be much easier on the barrel vs. a 7 short mag. Also some cartridges like the .243win. with that short neck/shoulder angle burns the throat out faster as well.Guess what when we do barrel life testing at all....we chamber them up in .243win. because it's that hard on the throat. The ammunition makers also don't like the round as well. They have to load for a velocity and a given pressure and once that throat starts to get the wear the barrel might still shoot accuracy wise but the pressure will start to vary to much and effect velocity and when that happens they have to pull the barrel from service. It's not uncommon for them to pull the barrel at about 800-1000 rounds in .243win.

Sometimes guys think the barrel has prematurely died but as has been previously pointed out a good cleaning can bring it back and or damage to the crown and a retouch up on the crown can bring the barrel back as well. When the bullet leaves the barrel you get a gas cutting effect from the powder and it will wear the crown. That's why I don't like the crowns with a sharp edge on the muzzles bore.....we put a 60 degree chamfer on the bore edge. The style of crown, 11 degree, flat, stepped recess, sporter radius etc...to me makes no difference but the chamfer on the bore edge helps.

Later for now.....Frank

Thanks for your time and insights, with the 60’ chamfer how deep is it? I had thought a knife edge crown was desirable and had heard about the chamfer but at what depth does it become the crown proper and is that for pure accuracy or longevity of the crown? Thanks regards Rich