Just got a good deal on a FAL that was jamming for the previous owner.  Got it home and got some good light on it and there's quite a bit of rust in the chamber.  Probably rust in the barrel as well (not worried about this one as much - but maybe I should...)

Thoughts and/or suggestions for best way to remove the rust w/out ruining the chamber?

I'm thinking of the following:

1) Chamber brush w/ WD40
2) Chamber mop with Evaporust
3) Chamber mop with JB paste (lightlly polishing kind of thoughts, but I'm scared most of this one)
4) Take to a gunsmith to kiss with a 7.62x51 reamer
5) Buy a new barrel

Haven't done anything yet except to spray a bunch of Remoil in there until I figure out what to do.

Otherwise the FAL looks fine.  I'm thinking either he didn't clean it for a while, or he shot some corrosive and didn't clean it.

Thanks

Use an M14 chamber brush and just go to town with a good oil.

You CAN use some sort of non-abrasive polish, but it probably won't be necessary.

Buying a brush and a mop from Midway today.

Thanks

I'll try to get some before and after pics for either a big thanks or regret....

"4) Take to a gunsmith to kiss with a 7.62x51 reamer "

A commercial reamer probably wouldn't even touch the sides of the chamber walls.  I also think you'd have trouble finding a gunsmith who owns a 7.62X51 NATO chamber reamer.  As stated above, a chamber brush spun slowly in a cordless drill should do the job, when used with your favorite oil.  If necessary, wrap it with #0000 steel wool to get good contact; you won't hurt anything by doing this, as long as you don't get carried away.

This- If you run a reamer into the chamber the only thing you will accomplish is to increase your headspace, which in a FAL is easily dealt with due to the locking shoulder design but it wont fix your issue with the 308 being a straight walled case..
Polish the chamber with the chamber brush/steel wool method but use ATF as a lubricant while you do. You are never going to get all the rust out. About all you can accomplish is polish off the surface rust.  I have cleaned up rough chambers in the past by taking a fired casing from the rifle and soldering a brass rod in the primer pocket. Keeping LB Bore compound from the shoulder and neck of the case lap the chamber VERY lightly. Take it easy here, you are not trying to remove any metal, just polish the chamber walls. By keeping the compound away from the neck and shoulder you should not change the headspace but check it with Go/No Go gauge to be on the safe side.
If it is pitted then you need to replace the barrel.

Many thanks everyone.

I hope to post results next week.

Can you tell how deep the rust is?  If it's minor surface rust, you can use a fine grit sand paper on a dowel rod by hand or on a drill.  Wet sand the chamber lightly with the paper oiled using machine oil or if you don't have that, a good stable gun oil.  DO NOT go into the shoulder of the chamber.  If you have rust there or if you have pits, get a new barrel.