I have a barrel indicated in the lathe. running less then .0002 off the ID of the bore. The OD of the barrel is about .025 out. Thats quite a bit more then Ive come across. Have you guys seen barrel this bad?
Kc
Kc
Gunsmithing Barrel runout ID compared to OD
- Thread starter ugsly
- Start date
Re: Barrel runout ID compared to OD
I have seen several factory barrels that were that bad or worse.
They were either barrels that were significantly shortened, or barrels that I was cutting up to make thread protectors.
I believe this is a big cause of shifting POI as a barrel heats and cools.
I have seen several factory barrels that were that bad or worse.
They were either barrels that were significantly shortened, or barrels that I was cutting up to make thread protectors.
I believe this is a big cause of shifting POI as a barrel heats and cools.
Re: Barrel runout ID compared to OD
Most of the custom barrels that I have used are around .005 or less. That seems excessive for a custom blank. Assuming it is custom.
Just based on what I have experienced. How is the muzzle end?
Regards,
Paul
Most of the custom barrels that I have used are around .005 or less. That seems excessive for a custom blank. Assuming it is custom.
Regards,
Paul
Re: Barrel runout ID compared to OD
I've seen lots of barrels like this. Both factory and aftermarket.
What's most interesting to me is that I see it more with button barrels than cut.
Which I have no idea why it'd be that way.
In any case, they all shot well enough so I guess its a problem that doesn't create a problem.
Good luck.
C.
I've seen lots of barrels like this. Both factory and aftermarket.
What's most interesting to me is that I see it more with button barrels than cut.
Which I have no idea why it'd be that way.
In any case, they all shot well enough so I guess its a problem that doesn't create a problem.
Good luck.
C.
Re: Barrel runout ID compared to OD
Yep. Ruger barrels are notorious for that.
That is exactly why you need to indicate off of the bore and not the O.D. like some do.
I cut a lot of barrels for suppressors. Some of them are bad enough that if I indicated off of the O.D. there would be baffle strikes.
Yep. Ruger barrels are notorious for that.
That is exactly why you need to indicate off of the bore and not the O.D. like some do.
I cut a lot of barrels for suppressors. Some of them are bad enough that if I indicated off of the O.D. there would be baffle strikes.
Re: Barrel runout ID compared to OD
Its really not supprising if you think about it. Drilling a 30" long hole (30"blank) the drill is going to walk some. Also the blank is going to have some runout itself depending on what length blanks they use. So is the run out in the bore or the blank itself? I dont think the barrel manufactures would indicate the bore of the barrel in then turn the contour. If that would even be posible to get the bore and od parallel the whole length of the blank. Just my thoughts
Its really not supprising if you think about it. Drilling a 30" long hole (30"blank) the drill is going to walk some. Also the blank is going to have some runout itself depending on what length blanks they use. So is the run out in the bore or the blank itself? I dont think the barrel manufactures would indicate the bore of the barrel in then turn the contour. If that would even be posible to get the bore and od parallel the whole length of the blank. Just my thoughts
Re: Barrel runout ID compared to OD
Years ago i got a 30" 6.5 full unturned blank from a major maker and cut it in half to make 2 XP-100 barrels, it was .067 out in the center. Turned both true from center and chambered. Both barrels still shoot 1/3 MOA.
Years ago i got a 30" 6.5 full unturned blank from a major maker and cut it in half to make 2 XP-100 barrels, it was .067 out in the center. Turned both true from center and chambered. Both barrels still shoot 1/3 MOA.
