So I procured what looked like was a very nice pre-27 / .357 Magnum, DOB early 50's a while back, and am encountering the following issue:

Fired brass falls out easily from 5 of the 6 charge holes, brass must be hammered out of one of the charge holes with a dowel or cleaning rod. Same thing happens with light .357 loads as well as powder puff .38 loads. Fired brass from offending charge hole won't even fit back into any other of the charge holes. Assembly # on cylinder matches # on barrel. Diameter of front end of fired brass from offending charge hole seems to be closer to .39 and slightly out of round, but close to .38 near the case rim. All this indicates to me that the offending charge hole is oversized somewhere near the middle or barrel end, and when shot the brass is expanding to the oversize charge dimension. What would cause this? Manufacturing defect? Bubba trying out his home polishing skills on a charge hole? (I can see no evidence of finish in this change hole being different than the others, who knows?)

Any way to restore this, or am I stuck with a 5-shot pre-27?

Thanks

You are describing a bulged chamber.

The most likely cause of this condition is firing an overloaded cartridge (too much powder, or the wrong powder) that slightly exceeded the elastic limit of the steel.

No fix for this except a replacement cylinder.

Unfortunately that sure is what it sounds like.

It is possible to overbore, reline, and re-cut the offending chamber (since it's an N-frame .357). I don't know how much this would cost versus cylinder replacement, if you can find one. Remember, replacement not a drop-in job.

Buck

Thanks all, there is no bulge visible on the outside of the cylinder, but the bulged chamber theory makes the most sense. Must have been a super hot load to bulge that cylinder. Time to start looking for a N frame cylinder that will fit into a Pre-27.

Succinctly, No. There isn't enough metal to allow this to be done safely, no matter what it looks like.

I can't speak to the safety aspects, but I have seen British Lend-Lease revolvers in .38/200 that have been bored, relined, and cut for .38 Special, and there's less cylinder wall to work with than an N-frame .357. Granted, there's lower pressure in a .38 Special, but I would be interested in your reasoning that there is not enough metal to fix an M27. An M29 handles roughly the same pressures with much thinner walls, so a steel composite wall of the same thickness as the original .357 wall doesn't seem so outlandish to me.

But, I can be educated, and my views can be changed.

Buck

The reason is that the liner, by itself, must be capable of containing the pressure of the cartridge. There is simply not room to install a liner thick enough to have the requisite strength.

This is the reason that so-called pistol caliber, and .22 caliber rifles can be re-lined safely, but high intensity rifles cannot be. If the liner fails then the barrel will fail. Surprising to many will be that .30-30 falls in the high intensity class. .357 Magnum operates at pressure levels not a lot lower than the .30-30, .35 Remington, and others.