Bad Barrel or Bad Chamber Job?

[TripleOption]

Looking for a bit of troubleshooting advice.

I have a 1:7 28" long Krieger barrel chambered in 6.5x47 on an Impact action. When I zero the rifle, I had to dial over 7 mils right to get it on paper (compared to the last barrel).

Additionally, the gun groups poorly (1.5" - 2" at 100 yards) and doesn't perform at distance. I was shooting 153 A-Tips @ 2670 FPS and had to drop the BC from .355 to .306 on my kestrel to get it to line-up at distance (1000 yards).

However, about every 3rd shot the bullet will go way high, which makes it seem like the bullet is actually flying at the correct BC.

My hypothesis is jackets are tearing (there is significant copper fouling in the bore) which is causing the BC to suffer.

My question is, is this an issue with the chamber or the rifling?

Any thoughts?

 

[Supersubes]

Nobody here is going to be able to determine whats wrong. Contact your gunsmith.

 

[TripleOption]

I have contacted my gunsmith, he's taking the stance that nothing is wrong with the chamber job and its the stock (despite BC being way off and barrel windage being off by 7 mils).

I have shot the barreled action in 2 different stocks with a different barrel on the gun and had no noticeable POI shift (besides maybe 0.1 mils in vertical shift).

 

[LR1845]

If you think its the barrel take the gun to a different smith if there's not one in your area either drive to one or send the barreled action to one and get a second opinion.

That said what scope are you using and is it in a mount or rings? I ask because I recently got a votex strike eagle in a warren mount in a deal that I could not get on paper at 100yds...long story short the mount was tweaked.

 

[Supersubes]

I have contacted my gunsmith, he's taking the stance that nothing is wrong with the chamber job and its the stock (despite BC being way off and barrel windage being off by 7 mils).

I have shot the barreled action in 2 different stocks with a different barrel on the gun and had no noticeable POI shift (besides maybe 0.1 mils in vertical shift).

What stock and scope? Contact krieger

 

[TripleOption]

That's probably the path I'm heading.

Stocks tried: MPA Matrix Pro & Foundation Centurion
Scope: Tangent Theta 5-25
Mount: MPA BA

 

[Supersubes]

That's probably the path I'm heading.

Stocks tried: MPA Matrix Pro & Foundation Centurion
Scope: Tangent Theta 5-25
Mount: MPA BA

Contact krieger. Theyre gonna want to look at it, which is good. Make sure you have some test targets.

 

[AllenOne1]

The first thing I would check is the scope mounting. Is something loose, a piece of dirt under the mount, etc. With the first thing you noticed being the windage off by 7 Mil that seems like a clue that something might not be mounted correctly.

Clean your barrel and make sure the corner edges of the lands aren't rough and coming apart using the dreaded borescope.

 

[Chris W.]

Scope mount sure seems like the easiest explanation.

 

[kthomas]

Is your barrel a tight bore?

 

[BurtG]

Was the barrel the only thing changed ?

 

[FisherT&C]

7 mills sure is a lot of wind correction even if the barrel wasn't timed. My first inclination would be an optics mounting issue.

As for the heavy copper fouling it sounds like the bore is too smooth or the throat is really rough.

Did someone go overboard with Bore Bright or another abrasive cleaner?

Can you look at the throat and see if it has heavy reamer marks or chatter?

 

[TripleOption]

The barrel was the only thing that changed in the setup (besides when I used 2 different stocks to ensure the bedding, as the gunsmith suggested, was a culprit).

When the same scope (not removed from rings) is mounted with a different barrel, that massive windage correction goes away.

The barrel hasn't seen any abrasives, only nylon brush and patch out. Plus this issue was present as soon as the barrel was screwed on.

I've attached some pictures of the throat and the rifling (about 2" past the start of the lands). And no, I haven't cleaned the barrel yet from the last outing with it.

 

[TripleOption]

Is your barrel a tight bore?

It's a standard .256 / .264 6.5mm barrel per the barrel coin or whatever it's called.

 

[oso1]

Soak patches with CLR and soak the bore down, also use a bronze brush and clean the bore back down to bare steel, will take you less than a 1/2 hour. It will not hurt your barrel and it certainly will not make it shoot worse than it is now. Or you can use any of the new expensive bore cleaners and a nylon brush and take days to clean the bore.

 

[BurtG]

I don’t think cleaning is going to fix 7! Mils windage.

Send it back

 

[oso1]

I don't think cleaning will fix 7 Mils either, but certainly see the bore much better

 

[Oldguy03]

I would inspect the scope mounting as a first step. If you believe the problem is with the barrel, take the pistol to another gunsmith. If none are in your region, you can drive there or mail the action with the barrel to one to get a second opinion.

 

[FisherT&C]

The barrel was the only thing that changed in the setup (besides when I used 2 different stocks to ensure the bedding, as the gunsmith suggested, was a culprit).

When the same scope (not removed from rings) is mounted with a different barrel, that massive windage correction goes away.

The barrel hasn't seen any abrasives, only nylon brush and patch out. Plus this issue was present as soon as the barrel was screwed on.

I've attached some pictures of the throat and the rifling (about 2" past the start of the lands). And no, I haven't cleaned the barrel yet from the last outing with it.

If the optics have been eliminated as a problem, there is a possibility the shoulder of the barrel is not square to the bore. If the bore is not in the ideal relative alignment to the optical plane that would explain the wingage discrepancy. Misalignment could cause anomalies you are interpreting into BC variance. As for the copper fouling, it doesn't look like anything exceptional at face value. I do see a partial land running up to the neck which could be an indicator of misalignment or a worn reamer.
The only way to be sure would be to indicate the bore and put indicators on the chamber and shoulder to measure their relationship to the bore.
Give it a good cleaning and get a second opinion.

 

[TripleOption]

Thanks for the help, everyone. I'm going to send it back to Kreiger and they're going to take a look at it.

 

[Supersubes]

Thanks for the help, everyone. I'm going to send it back to Kreiger and they're going to take a look at it.

Please come back and report the findings.

 

[Terry Cross]

Thanks for the help, everyone. I'm going to send it back to Kreiger and they're going to take a look at it.

Neither Krieger or any other barrel maker could screw up anything to make your barrel shoot 7 Mils to the right.
Even if you paid them $1K to do it on purpose, they couldn't.

Krieger may or may not be able to determine if there is any jacked up alignment problems with the breech end machining but they are not responsible for anything other than delivering a blank with a perfect bore. They manage to pull that off regularly.
I think Krieger is not the best place to start in this particular instance.
*I would say the same regardless of the barrel blank maker.

I predominately use Krieger for all my blanks. I stopped timing them 6 or 7 years ago because the most I have ever seen them out is maybe 3MOA from one another. I can bring 6 or 8 guns to test fire and move the same scope from gun to gun and still be on 8.5x11" paper at 100yds without having to touch the scope. So, my opinion would be that even if the blank was not timed in the lathe prior to doing the breech work, there is no way it would be anywhere close to that much out for POI deviation from center.

Don't waste time with a bore scope because good or bad, the bore condition is 100% NOT your issue.
Something is up with the machining on the barrel blank, the receiver Pic rail or the mount/optic setup (which sounds like you removed that from the equation already.

I think you would be better off sending the barrel to a shop that has a reputation for cutting accurate barrels (there is a shitload of them) and paying them to evaluate the machining done to the blank. If they find an issue, do not have them correct it. Have them document their findings and arm yourself with that to re-contact your original builder. Demand your money back or have them cut and install a new Krieger.

Great choice on cartridge selection. The 6.5x47L is a GREAT caliber. Inherently accurate and they are almost in 6BR territory with ease of load dev.

.

 

[PlinkIt]

Tagging in as I want to hear what the indicators say when it's put in the lathe...

 

[jwSubMOA]

Lord. Disregarding what looks like linear galling in the blank, (edited to avoid dogpile). In the throat you have radial tool marks that look like a somewhat dull reamer or not cleaning it out as the chamber was cut. For the sake of impartiality and competence, get it to a known good smith like LRI.

 

[Terry Cross]

Disregarding what looks like linear galling in the blank from the button. . . .

No button was used to rifle that blank.

.

 

[jwSubMOA]

Ah, single point. Still doesn't look great. Still think it's the chambering and fitting job.