Wondering what you guys have set for a limit on acceptable barrel curvature before you say no, won't use it or do you just time it out at 12 and rock on?
Gunsmithing Barrel curvature-what's acceptable?
- Thread starter Killswitch Engage
- Start date
I guess we have not seen one that has been far out enough to think there would be a problem. Have seen curvature from .001" - .200+"
so you have fitted a barrel with .200 runout? whats on average? would anyone fret over .025 curvature?
I put a 30" Pac-nor on a buddy's rifle (7mmWSM) in Palma conture that had just under .040" runout. I didn't like it but he said he wanted to try it. Its still their and is a sub 3/8" gun. Just clocked the high spot to 12 O'clock and let it eat.
My concern was that the barrel would have excess stress and start to walk after getting hot but it shoots great even for 10 shot groups.
My concern was that the barrel would have excess stress and start to walk after getting hot but it shoots great even for 10 shot groups.
Personally I would send a barrel back that had anything over .050" on a 30". At the very least call the company and explain the situation , I'd shoot it and if their was an issue then I'd take it up with the company.
.025 is nothing, I'd almost call that normal. Under .010 is rare. Granted I don't see as many as others, but I can say I would not think twice about 25. That has nothing to do with the quality of the bore, so if it came from a good name, run it and forget about it.
Galaxy S3 on tapatalk
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All the Bartlein's I've done recently have been under .015" and one was .006" at 30" long. I also have done two Benchmarks and one was .041" at 26" and the other was .038" at 27". The worst has been a Green Mountain at .134" and it still shot well but the bore was way off from center when cut from 26" to 22".
Zero runout is great and all...
But as long as the bullet enters the throat straight, and the crown is square/symmetrical to the bore, it'll shoot regardless of the runout.
But as long as the bullet enters the throat straight, and the crown is square/symmetrical to the bore, it'll shoot regardless of the runout.
I assume what you are speaking of is when the chamber end bore is dialed in, if you put an indicator rod in the bore on the outboard side and measure runout?
Or are you talking about if you chop off 10" from the blank, and the bore is no longer in the center of the OD of the barrel?
Or are you talking about if you chop off 10" from the blank, and the bore is no longer in the center of the OD of the barrel?
I wasn't referencing chamber runout.
My point is the barrel can do loop-d-loops between the chamber and crown, yet still shoot great - as long as the throat and crown are concentric to the bore at their respective locations.
I would generally agree with that as far as groups go and if the curve is clocked out vertical I don't have issue either. I was more curious what people found acceptable for crooked barrels.
I chambered a Bart 6.5 cal a few years ago and it looked like a jump rope...almost sent it back, but glad I didn't. Clocked it at 12 and it has to this day been the most accurate barrel I have owned.
We stock Bartlein barrels. Not that uncommon to see single digit runout, average would be something in the .015"-.040" range.
How do you guys measure that? Do you put the barrel on centers and look for runout anywhere along it?
Bartlein are far and away the most consistently straight barrels made. Krieger is second. Everything else if you get one .040 or under you are lucky. We have mounted up .080 total run out and it still shot great. Just have to clock them at 12 and you will be fine. I think if I got one with .100" run out it would have to go back.
I just fit one up that when the chamber end was dialed in the muzzle ran perfect. When I swapped it around and went to do the crown the muzzle end the chamber end was wobbling around .080" Like the end was bent. We cut the crown square to the last 2" of bore and it shot great.
I just fit one up that when the chamber end was dialed in the muzzle ran perfect. When I swapped it around and went to do the crown the muzzle end the chamber end was wobbling around .080" Like the end was bent. We cut the crown square to the last 2" of bore and it shot great.
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