Polishing A Chamber

[TXCOONDOG]

I have a .40cal pistol that my rounds are sticking in the chamber. I can see tool marks so I'm going to polish the chamber and feedramp with Flitz. I'm leaning towards using a .40/45 cal mop chucked in a drill.

Since this is my first time polishing a chamber, I'm looking for lessons learned or better methods recommendations.

[country gent]

The mop dosnt have the "strength to polish a true hole and keep it true. A wood dowel with a patch wrapped toa snug fit and a stop set for depth will do a much better job Run the polish tool slow rpms and faster back and forth speed so lines cross over each other for best polish. A 3/8 dowel and flannel patches wrapped tight should do nicely. I wouldn't worry about it unless there are feeding and function issues. I would be very carefull working the ramp and chamber as a lot of pistols now have unsupporrted chambers and to much may cause heads to rupture.

[contender1]

I'd contact DougGuy & let him do it. An out of round chamber can ruin things.

[TXCOONDOG]

I'm more than aware of the issues it can cause. I've used Doug for Reaming, etc. However, This is something I want to do.

[Bent Ramrod]

I take the stickiest case and sacrifice it. I drill and tap the primer hole 1/4"x20 tip, put a longish screw of this thread through the case from the mouth, and secure it with a nut on the outside. I lightly coat the case with Clover 320, chuck the screw in a variable speed hand drill and spin it in the chamber, pushing it in and pulling it out as it spins at moderate speed. Put the barrel in a vise and try to hold everything in a straight line while doing this.

I only do this for a minute, max, and only that long if the circular scoring on the chamber and shell is really severe. Twenty or thirty seconds should be enough to start, then clean the barrel, chamber and everything that the compound might have gotten on, and check the extraction. You don't want to enlarge the chamber unduly, just get the tooling marks lapped out.

Go slowly, check often, and don't overdo the Clover compound. A light coat will cut fine. Extra just squeezes into inappropriate areas and does no good.

[DougGuy]

I wouldn't polish it out with soft abrasives, I'd use a finishing reamer on it, a good finish reamer leaves NOTHING to polish afterwards! They cut *very* smoothly. And you would have a round chamber.

[EDG]

Don't mess with it unless you have a lathe.
Using a lathe to spin the barrel will permit polishing with 400 grit wet or dry silicon carbide paper. It should be used wet with a light oil and polishing the chamber should not take more than 2 minutes.

Before you polish the barrel find a sharp plastic stick like a swizzle stick and drag it down the chamber like a finger nail. If you cannot feel the tool marks do not bother to polish it.
Using a mop chucked in a drill is a bad idea. The soft mop has little surface control and will tend to polish the valleys just as fast at it polishes the ridges.
Ideally you only want to knock down the ridges (high points) of the tool marks.


I have a .40cal pistol that my rounds are sticking in the chamber. I can see tool marks so I'm going to polish the chamber and feedramp with Flitz. I'm leaning towards using a .40/45 cal mop chucked in a drill.

Since this is my first time polishing a chamber, I'm looking for lessons learned or better methods recommendations.

[TXCOONDOG]

You guys definitely gave me something to think about and I apreciate it.

[Tedly]

Wooden split rod , build size up to chamber dia w/ fine scotch brite . Note end of chamber , leas/throat , mark rod and avoid. Slow in handheld drill motor. More forgiving than abrasive paper and is usually enuff...My.02.

[lefty o]

I wouldn't polish it out with soft abrasives, I'd use a finishing reamer on it, a good finish reamer leaves NOTHING to polish afterwards! They cut *very* smoothly. And you would have a round chamber.

i agree with this 100%, a sharp reamer leaves a perfect chamber. if its a newer gun, id send it in under warranty.

[John Taylor]

Every once in a while I get a chamber that looks a bit rough. If it is not to bad I have an air die grinder that I use a split rod in. I put fine emery cloth on the end and wrap it around . Don't have a snug fit in the chamber, your just polishing it, not trying to make it bigger. The centrifugal force cause by the high speed will put the cloth on the metal. Keep moving it back and forth. The chamber should have a very slight taper to allow for easy extraction. I have had a few guns come in where the chamber is to pore to polish and usually end up lining the chamber.

[Geezer in NH]

Warranty time perhaps before you void it? That would be my first choice. When the maker can't fix it DougGuy