Barrel life

[Ggmac]

I've got a Hart , with 320 rds on it . 1-12 twist 28 long , still shoots an honest .25 in 5 shot with an occasional.20 5 shot at 100 yds .
Clean with Kroil and outers foam , reverse that , outers first then Kroil
It's a 1.30 straight. Very heavy esp since it's currently on a 4"x16" steel c channel .
The most shots thru a barrel was a Douglass XX CM 1-14 tw using 38 gr H-380 and 52 gr Berger BENCHREST . Fed match lr primers , win brass , was 1200 rds . It could no longer keep 1/2" at 100 .
We did set it back and took 4" off , had a 22" barrel that was under a 1/2" but soon opened up and couldn't keep the accuracy for more than a couple hundred rounds .

 

[msinc]

ironworker, how many rounds do you estimate have been down this barrel???? I don't know if I buy into some of the ideas offered in this post. The fastest thing I have ever had to burn out a throat was a 204Ruger shooting 32 grain bullets and a 1-in-13 twist...not heavy or fast twist by no means. On the other hand, I have put somewhere between 1800-2000 220 grain HPBT match bullets down the 1-in-10 twist barrel of a 30-06AI and the throat is not burned at all...and yes I have a Hawkeye. Burned up a few 243's shooting 70 grain or less bullets. Not sure I buy the bullet dwell time in the barrel causing it either. A bullet at the muzzle is still causing the throat to burn out????? Okay.
No argument that a longer bullet might make more friction heat, but again, compared to the powder burning it doesn't seem like that friction heat accounts for much.
Everyone is free to believe what they want, but I don't hear much about ELR rifles cooking throats the way I hear it about ultra high velocity varmint rifles. Maybe the long range guys just don't talk about it.
If the OP's rifle has a low round count I would say the barrel is puked up with copper and the bullets are slipping the rifling to keyhole at 25 yards. The 22-250 and the 220Swift have always been barrel burners, but not because they were used with long bullets and fast twist...that is something that is relatively new in practice. Another way of looking at it is that if long bullets and fast twist was so detrimental to barrel life then the 22-250 and 220Swift should have lasted a lot longer than they used to 30 years ago.

 

[370bc]

I would definitely JB bore paste the heck out of it before I would give up. I use a patch wrapped around a bronze brush on a cable (Dewy) on a cordless drill for the throat area. Then I Soak it for 3 days with wipeout, 3 different times. I had a Douglas 1-12 on my Kimber 243 that seemed like it was gone at times, only to come back to group after this treatment.

 

[Dusty Stevens]

ironworker, how many rounds do you estimate have been down this barrel???? I don't know if I buy into some of the ideas offered in this post. The fastest thing I have ever had to burn out a throat was a 204Ruger shooting 32 grain bullets and a 1-in-13 twist...not heavy or fast twist by no means. On the other hand, I have put somewhere between 1800-2000 220 grain HPBT match bullets down the 1-in-10 twist barrel of a 30-06AI and the throat is not burned at all...and yes I have a Hawkeye. Burned up a few 243's shooting 70 grain or less bullets. Not sure I buy the bullet dwell time in the barrel causing it either. A bullet at the muzzle is still causing the throat to burn out????? Okay.
No argument that a longer bullet might make more friction heat, but again, compared to the powder burning it doesn't seem like that friction heat accounts for much.
Everyone is free to believe what they want, but I don't hear much about ELR rifles cooking throats the way I hear it about ultra high velocity varmint rifles. Maybe the long range guys just don't talk about it.
If the OP's rifle has a low round count I would say the barrel is puked up with copper and the bullets are slipping the rifling to keyhole at 25 yards. The 22-250 and the 220Swift have always been barrel burners, but not because they were used with long bullets and fast twist...that is something that is relatively new in practice. Another way of looking at it is that if long bullets and fast twist was so detrimental to barrel life then the 22-250 and 220Swift should have lasted a lot longer than they used to 30 years ago.

He estimates 1500

 

[shoot4fun]

Key holing is, at least for me, not a telling factor for a worn out barrel. Make no mistake, there is something wrong but I would look for a suspect crown issue before declaring this barrel DOA.

 

[Ironworker]

I use KG1 for Carbon,then use wipe out and the accelerator stuff every time,usually let it soak overnight.(Bore guide as well) I get most of the copper out. Gunsmith chamber casted the chamber,he says the throat is fried. Maybe I'll get a slower twist bbl,the reason why this was a fast twist bbl and a #4 contour is because it was my predator rifle. More rabbits and squirrels and Montana Prairie Dogs around then coyotes. I shot it too fast and all my loads were hot loads mostly with Re#19. I do feel remorse,but I will not seek professional counseling. LOL

 

[Ironworker]

Maybe next BBL will be chambered in 22 BR ? Heard about longer barrel life with those. Would the bolt face need modifying ?

 

[Ggmac]

Maybe next BBL will be chambered in 22 BR ? Heard about longer barrel life with those. Would the bolt face need modifying ?

Good choice . If your only shooting to 350 yds a 223 will do it easily or even a 223 Ackley.
All 3 of my die hard 22-250 shooters have switched to 2 to the 22 br one to the 223 and another not so stubborn 22-250 shooter went to the 22 PPC
That's how I ended up with the old barrels . Sure we could have rechambered them but it was such a shooter as is and I only pull it out , all 32 lbs of it , every couple of years.
My vote is 22 br or 223 if you could change bolt heads

 

[Ggmac]

Key holing is, at least for me, not a telling factor for a worn out barrel. Make no mistake, there is something wrong but I would look for a suspect crown issue before declaring this barrel DOA.

1500 rds and keyhole, life is too short . I'd love to see a quality pic of that barrel .

 

[mikecr]

Using Ggmac's load:

This spreadsheet nails barrel life pretty well, and it doesn't care at all about the bullet itself.
Just amount of what powder, pressure & shot rate.

 

[msinc]

1500 rds and keyhole, life is too short . I'd love to see a quality pic of that barrel .

I'll go ya one better Ggmac, the idea that something could be wrong with the crown.......to make bullets keyhole at 25 yards......well, I haven't "seen it all", but I have seen 40 some odd years worth and I am not going to say it cant happen, but I will say that it is this simple...if a crown is so bad that it causes bullets to keyhole at 25 yards...you wont have to do no whole lot of inspecting and you for certain wont be on some forum asking about hints as to what's wrong. That screams of jumping right out at you and we aint talkin' borescopes and bright lights either!!!! While typing this I was just trying to imagine what I would do or use to make a barrel crown tumble bullets at 25 yards. It aint hit me yet, I aint even getting a dull vibe....I need whiskey.
Well, I need whiskey anyways...just sayin'

 

[onelastshot]

I love my 22-250, but shoot it sparingly. The sad reality of the 22-250 is the simple fact that they are barrel burners. I use a 12 twist and 55 grain bullets, many rely on a 14 twist. Like others, I often rely on one of my 223's and keep the 22-250 for longer range work.

It's a special caliber and are known for incredible accuracy; they just just have short lives.

 

[BenPerfected]

I'll go ya one better Ggmac, the idea that something could be wrong with the crown.......to make bullets keyhole at 25 yards......well, I haven't "seen it all", but I have seen 40 some odd years worth and I am not going to say it cant happen, but I will say that it is this simple...if a crown is so bad that it causes bullets to keyhole at 25 yards...you wont have to do no whole lot of inspecting and you for certain wont be on some forum asking about hints as to what's wrong. That screams of jumping right out at you and we aint talkin' borescopes and bright lights either!!!! While typing this I was just trying to imagine what I would do or use to make a barrel crown tumble bullets at 25 yards. It aint hit me yet, I aint even getting a dull vibe....I need whiskey.
Well, I need whiskey anyways...just sayin'

What’s the best whiskey?....or is it a Kentucky Bourbon?

 

[spclark]

What’s the best whiskey?....or is it a Kentucky Bourbon?

I’m partial to Bulleit’s rye myself... as much for their name as for the product itself!

 

[msinc]

What’s the best whiskey?....or is it a Kentucky Bourbon?

I’m partial to Bulleit’s rye myself... as much for their name as for the product itself!

Well fellas, "best" whiskey is always subjective...to me, best whiskey is the one in my hand right at the moment. That said, I like 15 year old Bushmill's me self. But, Virginia Gentlemen is a very close second, in no small part due to the price. To clarify, Virginia Gentlemen is actually Kentucky bourbon. They ship it from Kentucky to Virginia where is gets distilled again and eventually bottled.
Jim Beam "Maple" is the one most likely to make me a full blown alcoholic though...I even put that on pancakes!!!!!

 

[HomeSlice]

Using Ggmac's load:
View attachment 1050291
This spreadsheet nails barrel life pretty well, and it doesn't care at all about the bullet itself.
Just amount of what powder, pressure & shot rate.

Is that spreadsheet available online somewhere? I’d love to have it if you don’t mind sharing.

 

[Bart B.]

Here's my opinion on barrel life. Read posts #3 and #5 in this thread:

http://forum.accurateshooter.com/threads/barrel-life.3943336/#post-37134450

That's based on match grade barrels starting out averaging 1/4 MOA at 100 yards then averaging 50% bigger groups some rounds later. Mostly based on Sierra Bullets' data on test barrels and several competitor's experience and observations.

Hunting rifles with less accuracy may have twice the life, military service rifles with least accuracy have three times the round count for barrel life.

If longer bullet bearing surfaces cause more erosion per shot than shorter ones, anyone with valid data might come up with a change to my formula that compensates for it. Kevin Thomas, any idea on how to do this?

 

[Shynloco]

Yes, but a 22-250 is a barrel burner as is.

Then when you shoot hard and fast strings it makes the situation worse....

I used to have a 22-250 that I changed calibers on simply because as Steve stated, a 22-250 is a barrel burner and also ate my Lapua brass faster than any other calibers I was reloading for. Its another story that some calibers INHERENTLY have issues that other calibers do not have, such as burning out barrel and higher pressures when using the "heavies" which is why I think my Lapua brass got eaten so quickly....10 - 12 reloads. Compare that 22-250 caliber to a 30BR and makes you wonder why one eats barrels (shooting a .22 caliber bullet) and the other lasts a very long time shooting a 30 cal bullet.

Alex

 

[mikecr]

Bart we don't wear barrels out. We burn them out.
And regardless of bullet/bearing we can burn a 22-250 out in a single session (if rapid fire & no cooling). ANY BULLET

HomeSlice, PM your email & I'll send the file

 

[dcali]

Here's my opinion on barrel life. Read posts #3 and #5 in this thread:

http://forum.accurateshooter.com/threads/barrel-life.3943336/#post-37134450

That's based on match grade barrels starting out averaging 1/4 MOA at 100 yards then averaging 50% bigger groups some rounds later. Mostly based on Sierra Bullets' data on test barrels and several competitor's experience and observations.

Hunting rifles with less accuracy may have twice the life, military service rifles with least accuracy have three times the round count for barrel life.

If longer bullet bearing surfaces cause more erosion per shot than shorter ones, anyone with valid data might come up with a change to my formula that compensates for it. Kevin Thomas, any idea on how to do this?

With enough *good* data, you can fit a line through any number of variables. The ones I would start with would be bore circumference, powder charge, and bullet weight. Bullet weight captures both bearing surface length and barrel time, which I would expect would be good enough. But there's no reason you couldn't get finer grained with it - if the data exists (does Sierra test more than one bullet per barrel? I would assume so.) If there's a bunch of detailed data from Sierra or another large volume tester out there, I'd love to see it. The trouble is we have so little of that, and so much "well, it was shot out at 3000 rounds, give or take. I think". It's hard to do anything with that.