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hepburn45110
10-13-2016, 09:55 PM
What's the barrel life on a 1 7/16 dia. barrel!? (6ppc)

Wilbur
10-14-2016, 12:47 AM
I'm sure you're talking about "winning" life. If the barrel will win in its beginning, you'll need to start looking for another winner in about 1000 rounds. That's just a ballpark as nobody knows the actual answer.

hepburn45110
10-14-2016, 09:25 AM
Thanks

Dave Coots
10-17-2016, 10:17 AM
I've been told that the barrel that just won the 200 and Grand at the NBRSA Nationals has over 1,300 rounds through it.

Later
Dave

Wilbur
10-17-2016, 12:44 PM
The best barrel I ever had, both in accuracy and longevity, lasted a complete 2500 shots. I'm saying it was capable of winning for those 2500 shots. It entirely died (entirely) from one target to the next....Fairchance...nationals...the whole nine yards. Truth is, after the first 1500 shots, I knew I was taking a chance and it finally caught up with me.

Mike Bryant
10-17-2016, 11:47 PM
I've been told that the barrel that just won the 200 and Grand at the NBRSA Nationals has over 1,300 rounds through it.

Later
Dave

Dave, I'd say if anyone would know how many rounds the barrel had on that won the UL 200 and Grand, you would. Job well done. Congratulations again.

Mike

Jay Young
10-18-2016, 12:42 AM
I had a barrel on my LV/SP/HV where I won the 100 and LV Grand at the Raton Nationals one year and was in 2nd place the next Nationals in St Louis going into the last 3 groups and shot 3 big groups and thought the barrel went out, I had 5 shells in my loading block after the last target HV200 put them down range into the sighter and it was a .3XX @200, that barrel had 45XX rounds thru it, Also I had a barrel that was only a practice barrel until it had about 800 rounds through it then shot like wildfire set a couple of 200yds range records before it completely burn out 4-5" in the throat at 1100 rounds.during a match, in other words I have no clue....



Dave, I'd say if anyone would know how many rounds the barrel had on that won the UL 200 and Grand, you would. Job well done. Congratulations again.

Mike

jackie schmidt
10-18-2016, 08:24 AM
Dave makes a good point. Really good barrels tend to shoot at a competitive rate longer than barrels that were just average from the get go. Set them back, and they keep shooting.

Some barrels never are competitive. I arrived the Friday before the Nationals with a new barrel on my Rail Gun. I spent 3 days trying various combinations, and it was locked into about a .300 10-shot Agg capability. In short, it was dead on arrival. Nothing like going though 16 10-shot groups through two days of shooting knowing you are shooting a "second pager".

I left a set back barrel at home, (forgot to put it in the truck), one that was a proven performer.

My hats off to Dave and Larry. Their Unlimited performance was awe inspiring.

Wilbur
10-19-2016, 08:54 PM
Sorry that happened Jackie...wish I could say it won't happen again. I've known folks that would simply quit shooting when their rifle wasn't up to par but I could never bring myself to do that. I'm a bit envious of those folks that can just quit!! You could have saved a pound of powder and 200 bullets if you had just quit.

jackie schmidt
10-20-2016, 12:54 PM
Sorry that happened Jackie...wish I could say it won't happen again. I've known folks that would simply quit shooting when their rifle wasn't up to par but I could never bring myself to do that. I'm a bit envious of those folks that can just quit!! You could have saved a pound of powder and 200 bullets if you had just quit.

Wilbur, I am fortunate I had a couple of decent LV barrels. At least I was able to get enough back after that Unlimited fiasco to salvage a Top 20 overall. That made the 18 hour drive back to Houston a tad more palatable.

markharp
10-21-2016, 03:58 PM
Coots,

I would not trust that guy that gave you the round count!

Mark

Dave Coots
10-22-2016, 08:41 PM
Coots,

I would not trust that guy that gave you the round count!

Mark

No kidding.....:cool:

Later
Dave

BillBrawand
11-21-2019, 10:19 AM
Some time ago it was said walt bergers 22 barrel had 10 ths on it and still competive

GeneT
11-21-2019, 11:31 AM
I'm intrigued that a barrel would go from great to DOA in the course of a couple of rounds, rather than taper off in performance. Any idea what mechanism would cause such a sudden change? Or is it just that the difference between competitive and DOA is so small?

GsT

Asa Yam
11-21-2019, 02:21 PM
I'm intrigued that a barrel would go from great to DOA in the course of a couple of rounds, rather than taper off in performance. Any idea what mechanism would cause such a sudden change?
Barrel erosion. Think about it - powder burns at over 5000 F, despite the burn lasting for .8 microseconds (best guess) or so. As the gas expands, temperature drops. Still, the first 3 inches of the barrel gets hit by a wall of hot, reactive gas. Carbide and nitride gasses are the worst at attacking iron atoms in steel - they also produce lower melting or brittle compounds that flake off before the barrel reaches room temperature. Is there a fix? Cheapest answer is stop shooting. Not kidding. 5000 F temperatures reduce most compounds to their basic elements.

The above is a summary of a longer discussion from "Gun Propulsion Technology", which is Volume 109 in "Progress in Astronautics and Aeronautics". Editor is Ludwig Stieifel. Best bet in finding a copy? Engineering university library. Copies of the book are available online - starting at $95. See https://www.amazon.com/Propulsion-Technology-Progress-Astronautics-Aeronautics/dp/0930403207 .

Hope this helps.

GeneT
11-21-2019, 03:47 PM
Barrel erosion. Think about it - powder burns at over 5000 F, despite the burn lasting for .8 microseconds (best guess) or so. As the gas expands, temperature drops. Still, the first 3 inches of the barrel gets hit by a wall of hot, reactive gas. Carbide and nitride gasses are the worst at attacking iron atoms in steel - they also produce lower melting or brittle compounds that flake off before the barrel reaches room temperature. Is there a fix? Cheapest answer is stop shooting. Not kidding. 5000 F temperatures reduce most compounds to their basic elements.

The above is a summary of a longer discussion from "Gun Propulsion Technology", which is Volume 109 in "Progress in Astronautics and Aeronautics". Editor is Ludwig Stieifel. Best bet in finding a copy? Engineering university library. Copies of the book are available online - starting at $95. See https://www.amazon.com/Propulsion-Technology-Progress-Astronautics-Aeronautics/dp/0930403207 .

Hope this helps.

Thanks for the link! You've probably cost me $95... I understand the fundamentals of barrel erosion, but my real question was what mechanism made such an abrupt change, rather than a gradual loss of accuracy over a greater number of rounds? Barrel erosion has been occurring since shot #1, and is fine for e.g. 900 rounds, then somewhere between #901 and #905 everything goes to pot? That's a very interesting phenomena.

GsT

Wilbur
11-22-2019, 09:25 PM
I'm intrigued that a barrel would go from great to DOA in the course of a couple of rounds, rather than taper off in performance. Any idea what mechanism would cause such a sudden change? Or is it just that the difference between competitive and DOA is so small?

GsT

Could be that folks had rather say their barrel went south rather than say they went south. I'm probably one of those folks!