Magnum Cylinder In A Model 10 or 64?

[O2Guy]

I have a few pinned Model 10's and 64's and I have some odds and ends of parts including some K frame .357 Magnum cylinders. Has anyone ever put a Magnum cylinder in a Model 10 or 64? Other than timing, can anyone see any problems? I know all about flame cutting in a K frame with 125 and lighter grain bullets.

I know that a few Model 10-6's were made in .357 Magnum and the Models 13, 19, 65, and 66 are K frame Magnums. Are there any other differences besides the cylinder?

 

[scha]

I am not positive, but I think the length of the 357 cylinder is longer than the one for 38 Special. To fit a longer cylinder would mean cutting back the barrel that extends through the frame, etc. Not an easy change and there is also the strength issue. The 357s may get a different heat treatment at the factory.

Hope this helps.

Steve

 

[haggis]

IIRC, the frame of the K-magnums is reinforced at a few places to reduce frame stretching with magnum rounds.

Buck

 

[murphydog]

The standard reference states the model 19 had a "slightly larger frame in the yoke area" than a K frame .38. I would guess this was probably a strengthening issue. If the cylinder fits, I would probably not be inclined to use full-power .357s in it regularly.

 

[john traveler]

That's correct. The K-frame magnum cylinder is definitely longer than the M10 cylinder. To install a magnum cylinder in the M10 frame requires cutting forward the barrel stub and forcing cone to provide proper barrel-to-cylinder gap.

As to the question of K-frame strength, prior to the production of the M13 and M65 K-frame magnum, there was no need for the fixed-sight K-frame to withstand magnum pressures, and hence none were heat treated to that level. Now, the question is whether S&W produced all K-frames to magnum specifications, and only S&W can answer that but they probably won't.

I've had opportunity to examine several older model M&P revolvers that were rechambered to .357 Magnum. All were damaged with obvious signs of frame stretch, cylinder bolt cut dimpling, chamber bulges, and badly out of time.

The most common advice on your conversion idea is "DON'T DO IT"'

 

[jrm53]

357 Mod 10

John Traveler is right, if it was only going to be you shooting a revolver that had been modified like that and you only shot 38 specials it would be fine, as what can happen with someone else, I have a 101 Win. single barrel trap gun with a release trigger and I let a fellow shoot it telling him PLAINLY that onced you pull the trigger it will fire when you release the trigger, if you dont fire it the only way to keep it from fireing is to break it open, you can guess what happened we like to had a bad accident and now no one handles this shot gun but me. Jeff

 

[viceunit]

Many years ago a friend had the chambers of a model 15 reamed to accept .357 cases. With a short bullet, it could chamber and fire .357 rounds. I don't think anyone thought about heat treating of the frame and I cannot imagine even trying something that dumb today. It worked and the gun did not blow up, but I sure would not fire that thing.