When a barrel goes

[alton9]

I'm pretty sure my 9 twist .22-250 Brux has bitten the dust. Seemed to go all at once. Went from sub MOA at all distances to 4 to 6 inch groups at 70 yards!!!!!! I always thought groups would slowly increase in diameter, but mine just started throwing shots vertically fairly abruptly. Some high some low but not much horizontal dispersion at all. This was right at 1100 rounds, 37 gr. of H 4350 and a 75gr. amax. Just curious what others experience has been when a barrel gives it up?
And BTW, I did try a known good scope, another stock, check mounts, etc. Put the rifle back together with the original scope & stock with my .308 bbl & back to sub MOA performance.

 

[jonbearman]

I would have it borescoped to be sure it is done.You could rechamber if the rifling isnt gone.

 

[ShootDots]

I have never had a barrel just "completely go" all at once... Now a little background first. When I find that the barrel will not shoot near as well as it "used to", I change out barrels. Example: my 6mmBR, on a "relatively calm" day would get me (generally speaking) 597+ with usually 38 to 42 "X's" for my 300 yard scores in F-Open.. Once it started going I had a difficult time getting in the "low-30's" "X" count. Many of my "10's" would be on or near the 10 ring line.. The accuracy was beginning to slip on an "all too regular basis".. So when my rifles start to act like that, they are due for a barrel change.. They are still "good" per se>>>my gunsmith gets the barrel, he in turn "gives" it to a customer, who then pays for the machining work to his needs / desire.. At any rate, I don't let my barrels completely go>>>BUT I notice when they are well on their way down..

 

[sundance]

1100 rounds seems premature.I have an email from Sierra that they change out their 22-250 test barrels at 2800 rounds.They did not say who made their barrels.

Make it an Irish funeral.I always like them the best.

 

[M-61]

What seems very odd to me is "Seemed to go all at once." My experience with two barrels that gave up has been a gradual decrease in accuracy but nothing like your 4 to 6 inch groups at 70 yards. Both were hunting rifles that spent too much time on a bench shooting groups when I was a kid. 220 Weatherby Rocket and a 257 Weatherby. By the time I finished every possible check that I could and realized the barrels were the problem my groups had become unacceptable. None of this happened all at once. Both are hard on barrels. Both were fine hunting rifles, I just used them for something they were not meant to do. Long time ago.

 

[alton9]

Well, maybe it didn't go all at once, maybe some of those odd shots 150 or 200 rounds ago weren't me after all. I had hoped for more than 1100 rounds but maybe those 75's are harder on a barrel than 40's or 55's. I gave it a good cleaning to no avail, but I will have a friend look at it with a bore scope. It was just such a hammer when it was new.......

 

[gmorganal]

you have lengthened the COAL as the throat wore, Right?

 

[dkhunt14]

I had 2 Dasher barrels go prematurely. One at 350 rounds and one at 500 rounds. They both had a piece come out of the throat. They also went to shooting vertical. The one I cut off and rechambered and it went back to shooting like before. The other one had to many bad spots and I gave to a guy for a fireform barrel. You need to have it looked at with a borescope. Matt

 

[alton9]

you have lengthened the COAL as the throat wore, Right?

I have, but not in the last 250 rounds. It never seemed to lengthen much, but it started out really short. Was probably a reamer throated for lighter bullets. Do you think not chasing the throat for 250 rounds could cause accuracy this horrible? ( I'm not being smart here, I'm really asking).
Thanks,
Alton9

 

[jonbearman]

Out of pure curiosity,how do you take care of the barrel in regards to copper and a carbon ring just ahead of the chamber?

 

[fdshuster]

alton9: It's been my experience that when a barrel "goes", 3 "things" happen: (1) Groups open up with an increasing number of uncalled wild shots. (2) Cleaning becomes more time consuming because of greater copper fouling. (3) There is a pronounced drop in muzzle velocities, from when the barrel was new, using the same ammo.

When one of my 22-250 barrels failed, I also had an increasing number of keyholed shots on the target. All three were done at between 2200 and 2350 rounds fired. But those were all 14 twists with a steady diet of 50 to 52 gr. bullets.

 

[alton9]

Out of pure curiosity,how do you take care of the barrel in regards to copper and a carbon ring just ahead of the chamber?

Johnbearman,
I've cleaned every 75-100 rounds with Kroil, Barnes cr-10, & judicious bronze brushing. Every other cleaning it gets a good throat scrubbing with JB.

alton9: It's been my experience that when a barrel "goes", 3 "things" happen: (1) Groups open up with an increasing number of uncalled wild shots. (2) Cleaning becomes more time consuming because of greater copper fouling. (3) There is a pronounced drop in muzzle velocities, from when the barrel was new, using the same ammo.

When one of my 22-250 barrels failed, I also had an increasing number of keyholed shots on the target. All three were done at between 2200 and 2350 rounds fired. But those were all 14 twists with a steady diet of 50 to 52 gr. bullets.

Fdshuster,
1) I guess I have had some uncalled wild shots for the last 150-200 rounds. I thought it was me but now think it wasn't.
2) this barrel has never coppered up much & still doesn't
3) Hmmmm.... So that's why it used to take 9 MOA @ 600 & lately has been needing 10.5 MOA

Edit to add: Now that I think about it, last year I had to adjust my 200 yard zero at least once, maybe twice (shooting low). I'll have to try to find my old notepad.......
Thanks guys,
Alton9

 

[brian427cobra]

My 260 did exactly the samething, at first I thought it was scope, confirmed the scope was GTG, borescope reveal massive fire cracking, and the loss of a land, Bartlien tube had 4068 rounds.

 

[fdshuster]

alton9: One of the reasons that I chronograph my main load combinations when I have a new barrel chambered. The average velocities are entered into that barrels logbook. When the barrel starts to get high time on it, average velocities are most times lower ( usually around 200 to 250 fps), than when new.

 

[PALarson]

A lot of good and interesting stuff here, it is very doubtful that the barrel is tost at 1100 rounds with the load that you mention. In my opinion there are 3 reasons for the bad vertical groups that you are experiencing, 1 as has been mentioned the barrel may have launched a land, if so it's done, in order to determine that someone with a scope has to check it out. 2 fouling, that can and does cause bad groups. I have had a Kreiger that would foul and open up bad at 80 rounds, clean it and for a couple of rounds grouping was poor and then it setteled and shot great. It wasn't any good for XTC competition so it went on a hunting rifle, works great there, 3 this is one that I have happened recently to me, cases grow and if not trimmed will pinch at the mouth and cause high pressure and poor accuracy, mostly vertical shots which explains the high pressure. I actually pulled that barrel and installed a new one before I realized the real problem. Once the cases were properly trimmed it shot a 199-13X in FOpen, wish I had paid more attention to the case length. Ok, for what it's worth check these things out and find out if your barrel is actually gone, it no doubt isn't worn out, it may be damaged.
Paul Larson HM

 

[alton9]

Okay, I found my old notepad & it's interesting. I started adjusting my 200 yard zero last January at around 750 or 800 rounds. Looks like I was cranking it up 1/4 to 1/2 minute at a time every 75 to 100 rounds. At the time, thought it was an issue with my inputs on my Kestrel/Horus unit, looking back, it's a definite pattern.
I started struggling at 800 yards to keep 'em all on a 20"x20" steel plate in mid April @ 910 rounds. It would still group about an inch at 200 yds then. In May @ 987 rounds my 600 yd steel coyote was no longer a sure thing.
Didn't get to shoot much in the summer, but over the last couple of months I've felt like I was really struggling to make 600yd hits. Tuesday I tried my 20x20 at 900yds & couldn't achieve consecutive hits due to wild vertical. So today I put it on paper at 70 yds & got a rude awakening. I suppose I should've seen it coming, guess I was in denial. I've been wanting to try a Criterion prefit so I guess I'll call Northland after the holiday.
I have learned something though, a logbook is no good if you don't read it :
Thanks guys for making me think this through
Alton9

PALarson,
I'm going to have a buddy check it with a bore scope . These cases are fully prepped (inc. trimmed) & on their first firing. I had no trouble out of this batch & lot of brass when I first started on it.
Thanks