Gunsmithing Bore Scratch

[6.7Powerstroke]

I picked up my action with its new barrel yesterday and after I got home I realized it has this “scratch” roughy 1/4” from the end.
It goes roughly half way the bore, not super deep.
How much will it effect precision and accuracy?
Previous barrel was done by the same company and was capable of shooting 3/8 moa, I’m hoping this one will be too.
Best pics I could get

Update
I took it back to the gunsmith and they were kinda surprised to see it.
No one was positive what caused it but, they did fix it for free.
Off to the range now to see how it shoots

 

[Trigger Monkey]

Only way to know is to shoot it and stop pointing the rifle at yourself haha. Seriously though there's no way to tell how much it will affect accuracy without sending some rounds downrange. That being said, if there are issues it's a pretty easy fix to cut the barrel back a bit, rethread, and drive on.

Good luck.

 

[stello1001]

You asked how much this will affect accuracy... You have the rifle with you don't you? Go shoot the darn thing and find out for yourself...

 

[pabrousseau]

im pretty my smith would not have sent that out the door.

 

[Steel head]

That’s unacceptable unless you were charged less that $15 for the machine work.

 

[Praeger]

Affect accuracy, quite possibly. A potential nightmare to clean due to copper deposits, hell yes.

 

[A&8's]

Looks like they used a piloted cutter to cut the crown. Maybe the bearing/pilot seized? Or had a burr or sliver stuck in it.

As to accuracy: I'd take return it to the smith and at least let him see it in person, before you send one down the tube.

 

[E. Bryant]

I'd send it back. It takes less time to print a shipping label than it does to make a potentially disappointing range trip, and it's less stressful.

 

[Thud]

What E. Bryant said.

 

[RTH1800]

Nope, no way.

 

[ken226]

I can't imagine a gunsmith using some kind of piloted crown cutter when he's already turning, threading and chambering on a lathe.

I went to school for engineering and trained as a machinist, I've never been formally trained as a gunsmith.

I tend to be unaware of standard common gunsmith practices and mostly work by creating written setup sheets and plan sheets.

Is it a common practice to stick a piloted face cutting tool in the bore rather than single point the face and crown?

Also, is it just me, or does the crown look a little odd. I see the face cut clearly, but the end of the lands look razor sharp. I've always put a chamfer on the end of the lands and thought that was standard practice?

 

[natdscott]

I'm usually on the side of the smith and barrel, and I like to "just go choot it and see, ya whiny little internet armchair bitch".

But holy shit, boys. That's a DISASTER.

Take that back RIGHT now, and don't even chamber a round.


-Nate

 

[ken226]

So, here's what I'm talking about:

Random pic pulled from Google.


The actual crown is the chamfer at the end of the lands. All the rest of that is the muzzle face.

In the OPs pic, I see the face cut, and the funky looking scar, but not the actual crown chamfer.

Am I just not seeing it, or am I all fuqed up, been doing wrong all these years, and it ain't supposed to be chamfered.

The pic I posted is an extreme example, just to make clear the part I'm talking about. I typically chamfer the end of the lands, with .005 of the groove ends chamfered.

 

[RTH1800]

The concern I have is that the rest of the work was done by the same guy who did that. I'm thinking new blank, refund and call Chad at LRI.

 

[natdscott]

So, here's what I'm talking about:

Random pic pulled from Google.

The actual crown is the chamfer at the end of the lands. All the rest of that is the muzzle face.

In the OPs pic, I see the face cut, and the funky looking scar, but not the actual crown chamfer.

Am I just not seeing it, or am I all fuqed up, been doing wrong all these years, and it ain't supposed to be chamfered.

The pic I posted is an extreme example, just to make clear the part I'm talking about. I typically chamfer the end of the lands, with .005 of the groove ends chamfered.

You are focusing on the wrong part of this conversation.

Chamfer is fine. No chamfer is fine. I request both, depending on the weapon's purpose, and/or muzzle devices.

-Nate

 

[JLP.Payette]

I picked up my action with its new barrel yesterday and after I got home I realized it has this “scratch” roughy 1/4” from the end.
It goes roughly half way the bore, not super deep.
How much will it effect precision and accuracy?
Previous barrel was done by the same company and was capable of shooting 3/8 moa, I’m hoping this one will be too.
Best pics I could getView attachment 7215661View attachment 7215662

May be the picture but it looks like the crown is lop sided as well. Either way Id send it back as Id be more concerned about the chamber job.

 

[natdscott]

I'm thinking...refund and call Chad at LRI.

Hell. Call me. I can do better than that with a hacksaw and a file.

...and I have better tools than those, too.

-Nate

 

[ken226]

You are focusing on the wrong part of this conversation.

Chamfer is fine. No chamfer is fine. I request both, depending on the weapon's purpose, and/or muzzle devices.

-Nate

No, I didn't miss the scar, I saw it clearly.

I was probably just being too ambiguous. I word things diplomatically so minimize butthurt.

I was pointing out that the likely culprit was a cutter poked into the barrel, and that it probably caused other issues as well as the scar.

 

[AIAW]

Send it back. Not only unacceptable work, but the first time it doesn't shoot the way you expect it to the damage-demons are going to set in and you are back to square one.

Even if it shoots good on your first outing - doesn't matter. If it's ass on the 2nd, 3rd or 19th outing then there are those demons again... telling you that it needs to be repaired or replaced.

 

[FisherT&C]

looks like a scratch from a swivel type deburr tool, I'd give the guy a chance to fix it.