New Colerain barrel shooting left...

[Gobbletn]

Keith, I did notice while laying the barrel flat on glass that the flats are not the same as you are asking. With the breach end securely flat, the same flat does not lay flat at the muzzle. i.e. it is raised on one side. Making the barrel slightly "twisted? Its about 1/8 off! Never noticed this before. Hummm. I'm in Murfreesboro TN. This following is a edit... I blocked and bent the barrel, .062 or 1/16". Blocked it up, used clamps, calipers and prayers. I don't want to send it back if I can help it. My wood forward of the entry pipe is fairly thin and flexible, I can't imagine there is any pressure from the wood or lugs there. I also have a slot cut in each lug for expansion/contraction. I followed Ron Elert on a DVD kit gun build and actually had one of his guns to hold and handle thru my entire build. I will shoot today if wx allows and reply back. Thanks for your helpful, informative posts and replys.

 

[jerrywh]

Well, I wouldn't take my word for it, I have only built 310 guns in the past 30 years. :wink:

Yeah Mike. But this guy isn't you. There is a difference.

 

[jerrywh]

Even if he barrel is straight. When the flats are machined incorrectly the sights will be off.
I would like to know how he machined the flats twisted. That's a trick.

 

[David W.]

Keith, I did notice while laying the barrel flat on glass that the flats are not the same as you are asking. With the breach end securely flat, the same flat does not lay flat at the muzzle. i.e. it is raised on one side. Making the barrel slightly "twisted? Its about 1/8 off! Never noticed this before. Hummm. I'm in Murfreesboro TN. This following is a edit... I blocked and bent the barrel, .062 or 1/16". Blocked it up, used clamps, calipers and prayers. I don't want to send it back if I can help it. My wood forward of the entry pipe is fairly thin and flexible, I can't imagine there is any pressure from the wood or lugs there. I also have a slot cut in each lug for expansion/contraction. I followed Ron Elert on a DVD kit gun build and actually had one of his guns to hold and handle thru my entire build. I will shoot today if wx allows and reply back. Thanks for your helpful, informative posts and replys.

Send it back to Colerain. Problem solved.

 

[Birddog6]

That solves the barrel problem, but not the total problem. Then he has to fit the new barrel into the stock & that can lead to gaps & etc. And most likely it is not going to drop in, & if it does, you won't like the fit you now have.....

Also, this is why I shoot ALL of them as soon as I have a lock, trigger & barrel in. If I have to change barrel, I want to do it then, not when it is finished.

Keith Lisle

 

[David W.]

That solves the barrel problem, but not the total problem. Then he has to fit the new barrel into the stock & that can lead to gaps & etc. And most likely it is not going to drop in, & if it does, you won't like the fit you now have.....

Also, this is why I shoot ALL of them as soon as I have a lock, trigger & barrel in. If I have to change barrel, I want to do it then, not when it is finished.

Keith Lisle

No, it doesn't solve everything, but it takes the biggest problem out of the picture.

 

[Mike Brooks]

Even if he barrel is straight. When the flats are machined incorrectly the sights will be off.
I would like to know how he machined the flats twisted. That's a trick.

I have had several colerain barrels with a twist. Didn't seem to bother anything. Also Some of their big musket barrels are not bored concentric....I don't know how they do that either.

 

[Gobbletn]

Guys, after the bending, I recentered my sights and shot today. Prior to bending I was 7-8" left at 25 yds. Different loads produced similar results. After bending and centered sights I am 1-2" left. I tapped both front and rear sights and now I am zero! I wish the sights were dead on but this barrel has some obvious problems but if it keeps on slinging them consistently I'll keep it... Thanks for inputs...

 

[William O.]

Thanks for the links. I've never heard of barrel bending before and frankly it sounded like a disaster waiting to happen. I'm reminded of many cartoons from my childhood in which the barrel of a rifle was bent or tied into a knot or some other such thing.
:rotf: Yea, I remember Bugs doing that to Elmer's shotgun

I guess it's not as dubious of an idea as I originally thought but I don't think I'll be bending any barrels myself anytime soon.

No, it's not for folks like me to accomplish with two "C" clamps and the kitchen table but done right it a legitimate solution to a problem.

 

[William O.]

Glad to hear that!

 

[Dphar]

All this talk about barrel bending sounds alarming to me. I don't have much experience in this field so if you guys really know what you're talking about when you suggest bending a barrel go ahead but I've got a few questions.

How far off to the left is the gun shooting right now ?

Would a bent barrel still produce good groups ?

any chance this is not an artifact of the gun itself but of the shooter ? ?

Fred D said that .13" of bend would move a group by 8" at 50yds, I don't know much about Colerain barrels but could the forearm of the stock really bend a barrel by 1/8th of an inch ? It seems like it would take a lot of torque to bend a steel barrel by that much.

If it's bent and it really is new I would send it back rather than take any chances bending it back the other way.

What if the counter bend doesn't straighten the barrel but instead puts an S-curve in it ?

I started a thread about buying cheap barrels on eBay and several members chided me about skimping on the important part of the gun but this seems like an even worse idea to me. How prevalent is barrel bending ?

The barrel is probably bent now. Other wise the sight would be centered and the POI would match them.
You think these things are straight when they get done machineing them? Most are not.
Go down this page and you will find an anvil (usually used with a lead hammer) and an barrel jack for straightening barrels.

Then watch the video here
http://www.nij.gov/training/firearms-training/module04/fir_m04_t06_04.htm
Dan

 

[jerrywh]

Barrels are straightened before they are rifled. I know of no way to straighten a barrel after it is rifled other than just plain guessing.

 

[Powerkicker]

Modern m16 barrels are often straightened when attached to an upper receiver at the Factory. They check them on a fixture and the tweak them.

 

[roundball]

Just as an aside, it's interesting the differences in all of us.
If I knew I had a new factory barrel that was out of specs, I'd never be satisfied with it until it was fixed or replaced by the manufacturer...whether or not it did better after home-bending, it would still be "defective" in my minds eye and would always nag at me.

Laser guided barrel alignment machines are in use by at least some major barrel manufacturers and assuming Colerain has such a machine, they would have tweaked it to specs...and possibly benefited by learning that a quality defect "escape" had occurred, maybe reviewed/tightened up their final testing or something.
Just my particular .02 cents...

 

[jerrywh]

QUOTE--"Keith, I did notice while laying the barrel flat on glass that the flats are not the same as you are asking. With the breach end securely flat, the same flat does not lay flat at the muzzle. i.e. it is raised on one side. Making the barrel slightly "twisted? Its about 1/8 off! Never noticed this before."

If this is the case the sights would have to be set aside to compensate for the twist in the flats. Very likely the barrel is not bent. The flats are just twisted. Weird, I have never heard of that before. I would like to know how that is possible. 1/8" is a lot of twist as you describe it. Just curious. With that much twist how does the forearm look? It must be twisted also. I would have noticed that before I inletted the barrel. When you laid the barrel on the glass was the glass all one piece. Is the glass twisted? Nothing is impossible. Well almost nothing.

 

[hoochiepapa]

Jerry, all due respect but I have a Getz that has twisted flats. I was having a hell of a time inletting it, and my machinist friend took it down to his "flat" table, and sure as shootin' the flats were twisted, not 1/8", but almost.

 

[Billnpatti]

Okay, DO NOT....I repeat, DO NOT do anything to the barrel until you talk to the seller. :shake: The people from whom you bought the kit would be the first people to contact. If the barrel needs to be replaced, and from what you said, I think that it may need to be replaced, it must not have had any tinkering done to it. :nono: You must be able to send it back in the same condition that you got it. Let them look at it and replace it if that is what it needs. If you tinker with it, by bending as some have suggested, you will most certainly, void any warranty. Make a phone call and talk with the company from whom you bought the kit. They should take care of the problem but may possibly have you talk to the barrel manufacturer. But whatever you do, talk first before doing anything else. :thumbsup:

 

[jerrywh]

Mike. I'm not disputing the fact that it is twisted, nor your's. I would just like to know how that comes about. Those barrels are plained or milled octagon after being rifled. If they are mounted on centers in a indexing fixture, they must be slipping in the fixture while being milled or plained. Mounting a rifle barrel in a indexing fixture is not a very solid way to mill it. It needs more support than that. If it is clamped on a table how can it turn? Where is that engineer around here? Zonie---help!!

 

[Mike Brooks]

Mike. I'm not disputing the fact that it is twisted, nor your's. I would just like to know how that comes about. Those barrels are plained or milled octagon after being rifled. If they are mounted on centers in a indexing fixture, they must be slipping in the fixture while being milled or plained. Mounting a rifle barrel in a indexing fixture is not a very solid way to mill it. It needs more support than that. If it is clamped on a table how can it turn? Where is that engineer around here? Zonie---help!!

My guess is their pushing the machinery too hard and the barrels are warping. Another thing that bothers me is hollow flats on colerain barrels. Must be a worn out planer blade...... Just filed one out an hour ago, lots of work when the flats are hollow. :shake:

 

[Birddog6]

My first thoughts on one with twisted flats would be wear in the milling machine, or the clamping device is moving or has wear.

Keith Lisle