Scratch in chamber

[jsali]

I don't know how it got there. However there it is. There is a shallow scratch maybe a quarter of an inch in length, hockey stick shaped near the back of the chamber (all I can think of is there was something on a cartridge case when it was chambered). It doesn't seem to effect accuracy or chambering however it does leave a shallow imprint on fired cases. Will this cause me problems or is it still good to go?

-John

 

[Gandolf1]

You got a picture Johnny5?

 

[jsali]

I could get a digital of a case this evening, however I don't know if I could get a snapshot of the inside of the chamber, it's in a rough spot to see.

-John

 

[Fiftydriver]

Johnny5,

If its leaving a mark on fired cases its a pretty significant chamber flaw. I would take it to your smith and see if he can carefully polish it out. Don't take it to a guy that is going to increase the chamber diameter by 0.010" but in most cases, scratches can be carefully polished out completely or at least to a point where they are insignificant.

Function wise there should be no great problem but I would get it fixed anyway.

Is this a factory rifle or custom?

Kirby Allen(50)

 

[jsali]

It's a custom.

-John

 

[Fiftydriver]

Send it back to its maker and give him first shot at fixing it. May give you a break on price as well.

Kirby Allen(50)

 

[jsali]

I had some 400 grit wet/dry paper and split a wooden dowel (1/3")at the end. Then I folded a small patch sized piece of the paper and put it into the split. I put the dowel into the chamber and gave it about 20 spins by hand. The only pressure on the paper was the paper trying to unfold. It polished the inside of the chamber up. The scratch is still there however it looks slightly smoother and there is no burrs on its edges. The chamber was tight to begin with and I could not detect any loosening. Is 400 grit paper too fine. I have heard that if the chamber is too smooth the cartridge will not grip on expansion. Any input would be appreciated.

-John

P.S. The chamber is .300 win mag.

 

[Fiftydriver]

Johnny,

I use 600 grit W&D to polish my chambers so I guess that tells you my opinion on the matter. I have even used 800 grit finishes but saw no difference in performance for extraction so I figured the extra time was wasted.

In my opinion, 400 gr it a little rough. Make sure you get all the residue out of your chamber before you fire the rifle. Clean out everything in the bolt locking area as well.

I have seen where there was paper residue in the bolt face that when fired etched the entire chamber and required the barrel be pulled and totally repolished.

Just make sure she is clean and see how the fired case look.

Kirby Allen(50)

 

[jsali]

Will do, I cleaned it really well already and I will do it again. The chamber looks smoother than it was before that is why I was asking. THanks for the response.

-John