Question about potential throat issue on brand new Accuracy International replacement barrel, pic's attached

[matt33]

I just received a replacement barrel for my Accuracy International AT-X from a reputable vendor. I have not shot the new barrel yet, or even installed it.

The original barrel is well over 3,000 rounds, while it is still shooting acceptably well, I realize I'm on borrowed time as I shoot a lot.

I hate to be "that guy" with a borescope, but I was looking at the leade/throat area, and it has some marks where the rifling begins that concern me. I'm attaching a photo below, there are virtually identical marks on all 5 groves. I don't recall these marks on the original barrel. I also have a newer Proof Research Barrel that does not have any marks like these.

I really don't care as long as the barrel hammers, but the factory barrel set a pretty high bar, it has historically shot in the .2 - .4 MOA range with handloads for 5 rounds at 100 yards.

Are these marks in the rifling a cause for concern? Do you think I should contact the vendor? Should I just shoot this thing? What would you do?

It's an $1,100 barrel using a Bartlein blank, I just don't want to be disappointed with its performance and be stuck with it if there's an issue.

Borescope video:

 

[loveha]

That pic is blurrier than big foot.
Could be oil. Could be tooling mark. Punch the barrel, and get a better picture.

 

[matt33]

That pic is blurrier than big foot.
Could be oil. Could be tooling mark. Punch the barrel, and get a better picture.

This borescope is an Amazon special. I spent the rest of my money on ammo. It's all I have. I did punch the bore, that's after. It is definitely tooling marks, there are five of them that look identical where each groove starts near the throat

 

[matt33]

Here is a YouTube link of the video
Borescope vide

 

[____________]

Here is a YouTube link of the video
Borescope vide

Looks like a little burr. Clean the barrel and shoot it. The first shots will probably clear the swarf out. If the barrel does not shoot after 20-50 rounds call your gunsmith.

 

[Baron23]

Yeah, sort of looks like when cutting the leade it tore a bit of the land but I have zero idea why that would be on all five. And I would sort of expect that more on the free bore end of the leade where it’s thinner but I’m in no way a gunsmith.

I do agree…shoot it and see and shooting it will erode the leade and should smooth that out.

Best chamber I have seen w my limited experience came from @AccuSol-ERN. Ends of leade looked like they were drawn w a straight edge and a drafting pencil. Of course, that lasts until the first rounds go down the barrel. lol.

But more seriously, I like to see attention to detail in work I pay for and Ern provided that in spades.

 

[StraightJacketArmory]

Its super hard to see with the oil and images but it looks like the reamer might have slightly been undersized. When the reamer cleans it out completely that goes away. Sometimes it could be an old reamer or maybe its just a touch small.

A Lot of reamers sometimes leaves a small burr which is fine, after they shoot a few that is usually gone.

I would put 5-10 rounds down it and see what it looks like. I'm sure if it is truly a reputable shop if there is any issue they will make it right. But again shoot a few and see what it does. Those Bartleins all hammer if they are dialed in.

 

[StraightJacketArmory]

Yeah, sort of looks like when cutting the leade it tore a bit of the land but I have zero idea why that would be on all five. And I would sort of expect that more on the free bore end of the leade where it’s thinner but I’m in no way a gunsmith.

I do agree…shoot it and see and shooting it will erode the leade and should smooth that out.

Best chamber I have seen w my limited experience came from @AccuSol-ERN. Ends of leade looked like they were drawn w a straight edge and a drafting pencil. Of course, that lasts until the first rounds go down the barrel. lol.

But more seriously, I like to see attention to detail in work I pay for and Ern provided that in spades.

It’s going to be in all 5 as the reamer has to clean them off. Usually when it’s torn it means the reamer could be dull or undersized a little.

Here is a picture of our chambers with it cleaned out completely

 

[ShtrRdy]

It sure looks like there's a burr on the leade. Sign of a full reamer. I would first contact who you bought the barrel from and ask for guidance. They will likely ask you to shoot it and see if it performs acceptably.