Bullet to throat fit:
FYI: Although 22 revolver cylinders have charge holes because .22s use heeled bullets (same diameter as the cartridge case and the last modern cartridge to do so), all charge holes are not created equal.
Charge holes are usually bored thru in one diameter; think cap and ball and the heeled bullet era of the late 1800s.
As you all know, chambers have a shoulder where the case neck ends and a slightly smaller diameter where the bullet throat is located at the front of the chamber, as do all center fire cartridge chambers.
However S&W .22 chamber throats can be the cause of difficulty to chamber rounds due to the bullet plating, color coating, wax, or even crud a bit too thick to enter the throats w/o a little muscle and frustration. Why? Because S&W chamber throat areas have a slight taper, kind of a modified charge hole design.
S&W chambers are seldom truly under sized, they're tapered for accuracy.
Stick your .22s into the front of the cyl chambers backwards to test your ammunition's bullet fit in the throats. You’ll also find that some manufacturer’s .22 ammunition will chamber completely case and all from the front end but with others the case will not enter the throat!
Fixing tight chambers:
I always attempt to fix problems with the very least invasive method.
Also I would never tolerate a sixgun that was finicky with certain brands of ammo, especially these days when certain specific brands are so hard to find. Having said that, I do recognize that each gun has its own preference for the best accuracy and I will cater to that.
But the fact is, many chambers come from the factory with less than satisfactory chamber finishes. This is exacerbated on a nickel gun because the plating does add a smidgen of extra thickness on the metal surfaces and can make chambers a little extra tight.
Look in your chambers with good light and a 5X glass. You'll see the factory machining marks, those are your problem. They not only grip the sides of your cases like friction tape, they collect fouling like a magnet.
However in my 59 years of shooting experience I've never had to resort to a gunsmith or any added tools expense to fix chamber extraction issues.
A simple inspection for burrs is an excellent first thing to do. Quite often one burr in one chamber make all six chambers extract too hard.
Then I load and shoot one round in each chamber and extract that one case to find any chamber or chambers with a specific problem or a burr.
Then I polish all chambers gently. The simplest for me is 800 to 1000 grit paper wrapped around a wood dowel with a slit in it, just slightly smaller than the chamber diameter. Mount in a Dremel tool or small power drill and spin in the chamber. It only takes a couple of seconds per chamber.
You can even go up to 2000 grit, or use Flitz on an S&W barrel mop, the chambers will look like mirrors!!
One caution is to stay out of the chamber throats, you don't want to affect the shoulder or throat area.
Of course .22s chambers are simplest to do because they don't have actual chambers, they have charge holes, no shoulders, (not .22 Magnum chambers, they have shoulders).
The secret to success is to keep the dowel moving in and out of the chamber so you keep the chamber walls straight. If you don't move the dowel or any polishing device for that matter, in and out, you risk creating waves or wallows in the chamber walls and cases will stick even worse.
But as I said only a couple of seconds is needed so there's little risk of the problem occurring and no risk if you move in and out using a dowel.
The risk is greater using polishing compound on a patch because it doesn't have straight sides. Especially if used with a power tool and not moved in and out.
You don't need or want reaming, even finishing reaming; you just get new machining marks and slightly larger chambers for the cases to bulge. All you need to do is a simple little polishing:
1. By hand with a cleaning rod and the wool cleaning mop supplied with Smiths. Apply Flitz, Semi-Chrome or Mother's Mag Wheel polish. This method will take some time.
2. This is actually a proper application for a Dremel tool when used correctly! And much faster. Mount the mop in a Dremel tool. The critical issue is to keep the mop MOVING IN AND OUT while spinning in the chambers to keep the chamber walls perfectly straight and not create wallows.
3. Make a small mandrel for the Dremel from a piece of old cleaning rod, Chinese chopstick, or the like with a split cut in the end. Use a piece of 2000 grit wet or dry paper in the split and wrapped layers around the mandrel until it's a snug fit in the chambers. Use a light oil and again, keep it MOVING IN AND OUT until chambers are polished. Methods #2 and #3 of course will take much less time.
I'm sure you'll have no problems after that.
