rust in rifle chamber, removal/fix??

[saskgunowner101]

So I was talking to a buddy from out of town last night, and apparently he has (we think) a rust problem in the chamber of his rifle. The rifle is a Parker Hale in 308 NM. Anyways, he tells me the rifle was fine up until the year before last. He put it away after hunting season, took it out in the summer and discovered it had a problem.

When you fire the rifle, the bolt doesn't want to open very easily, and the case comes out with weird blotches, orange colored. I asked him if it happened every time, but he wasn't keen on firing it after that.

I asked about the primer condition etc, and he said they were same as the last 10 boxes. I was thinking out loud maybe a spring or something inside the bolt had broke, but most likely the chamber is the problem??

He's got it drenched in G-96 right now, I told him to grab a 50 or 54 cal bronze brush and spin it slowly in the chamber up and down while oiled to see if that may help. Where does he go from here to gently polish the chamber without damaging it? Could he next wrap copper chore boy around the brush to get more aggressive if the brush doesn't fix the problem?

What polishing compound would be the next step? I've polished a fussy mold with toothpaste and baking soda, so I know it doesn't take much of a grit.

He tells me a smith down there wants around $500 to fix it, so he'd rather have a go at it before spending that. Any thoughts appreciated.

 

[teenahlake]

Probably just as easy to have it rechambered to 300WM, I wouldn't think that just pulling the barrel and setting it back one turn then rechambering should cost more hand 200ish.

 

[Revlover]

An appropriate brass brush wrapped in a bunch of steel wool on the end of a cleaning rod which is inserted into a drill.

Plenty of oil, and you should be good.

Same process to polish a shotgun chamber, or Mosin/SKS chamber to clean out the laquer from surplus cases.

 

[gunrunner8]

Probably just as easy to have it rechambered to 300WM, I wouldn't think that just pulling the barrel and setting it back one turn then rechambering should cost more hand 200ish.

I would guess that particular chamber might have deep rust pits and either 308NM or 300Wm having very small case taper requires more than one turn to set back the barrel.
Ea turn in Mauser thread equals .083". Over the lenght of 2" of those case bodies the taper is only .020" or so. Each .083" advancement of chambering reamer in this case will only "scrape" .00042" per side or less than half a thou, not enough to clean even moderate chamber rust.
If that barrel has only short flange (feather weight style) like most Mausers then that barrel might be a toast and $500 price for rebareling is not out of line IMHO.