I’ve got a new JGS 22lr “Sport Finish” reamer. Would I be OK to use that on my 34-1 with tight chambers? Or do I “need” a Mason? The JGS has a fixed pilot if that matters.

I just have my gunsmith polish the chambers on my Smith 22 revolvers. They are routinely rough and undersized out of the factory: a characteristic if Smith 22 revolvers.

Takes him about 10 minutes using a drill press, a little polishing compound and 22lr case.

I’ve asked him why he doesn’t use a reamer. He thinks it’s unnecessary and overkill.

The reamer makes the chambers the size they should have been in the beginning. No overkill there. You can polish the chambers, but they will still be undersized, and may not be round or straight holes. Some people erroneously think that tighter chambers than normal specs. make the gun shoot tighter groups. There are many levels of undersize, depending on how worn out the reamer was when it cut that that chamber.

The OP's reamer is likely to be for a chamber that is one piece with the barrel, so would have a smaller pilot than a cylinder reamer to fit in the rifling. It will probably work OK, but technically is not the right tool for the job. You can wrap some Scotch tape around the pilot for a closer fit, or just run it as is.

__________________
protocalldesign.com

I’m home now and have very gently “trial fit” the reamer to the revolver. The pilot is a touch loose from the front of the cylinder. It’s definitely going to cut the chamber larger. This reamer will definitely not “drop in” to these chambers, which tracks with how tight the rounds are to chamber.

I am a bit nervous about using the reamer so I tried some mother’s mag polish with a 22 cal bore mop yesterday. Using a drill set on low speed I polished the **** out of the chambers on the 34-1 4”. Remington Golden bullets will now drop in and fall out. Winchesters still require thumb pressure to chamber.

Figured I could always remove more metal, much harder to put it back.

I use a Manson Chamber Reamer which is sized exactly for reaming the Chambers on a 22 LR revolver. I have never heard of the term "sports reamer", don't know who made it and what size it is. Therefore, if it were me, I would spend the $50 bucks or so and get a "known quality and quantity". If you can confirm that the reamer you have available is the correct one for the job and it is in perfect condition, then by all means. Other than that, I'd certainly want to know precisely what I was using.

Taking a chance on ruining a perfectly good vintage S&W revolver is not something I'd take a chance on - just my personal opinion of course.

Running a properly sized piloted reamer by hand likely won't damage the forward portion of the cylinder. Running the same piloted reamer in a mill quite likely will damage the forward cylinder portion. For 1911 barrel purposes, our shop procedure was to carefully grind away and round the vestigal pilot end. We also used Manson reamers; good stuff.

Remember never to turn a reamer backwards as it will likely kill it.

A used 34 that I acquired has loose chambers, possibly from a bigger reamer after pistol left the factory. I have yet to need to polish a .22LR revolver charge hole. If I do, I think I will try the fired case and very fine lapping compound first.

I have polished the chambers on my K17 with a .22 mop and jewelers rouge. Worked like a champ. Some of the chambers need more attention than others. Go slow and check often. Several trips to the range might be called for to see how it works after getting dirty. Go sloooow!

__________________
USMC 69-93 Combat Pistol Inst.

I had a S&W M 17 & 18 reamed by my gunsmith years ago. Now have a 34-1 that needs it, and the smith has passed. I bought the reamer, just haven't done the job yet. There are posts here that describe the process, hence I bought the reamer.

__________________
Kevin in Oregon

I would try polishing before I reamed it. Better not to take off metal as it can not be put back. Polishing just works on the very surface metal.

__________________
USMC 69-93 Combat Pistol Inst.

Polishing the chambers with Flitz or JB Bore Compound won't do much at all. Been there - done that! After trying this numerous times, - don't waste your time! Get the Manson Chamber Reamer and be done with it.

Jewelers rouge and a mop worked for me. For others their mileage may vary. Not a waste of time in the chambers of my S&W.

__________________
USMC 69-93 Combat Pistol Inst.