I have a 60s-70s J frame S&W 3" barrel revolver my much better half gave me as a birthday present a few years ago. I've shot a few jacketed rounds through it, but don't really want to beat it up, just take her out for some occasional range fun. Problem is, jacketed Hornady's and Speers will not go through the cylinder throats...the bullets measure 0.357 consistently. I'd like to just shoot cast with this old gal, best to size down, maybe .356? I'm kinda new at revolver accurizing, so any tips are welcome.

Exactly what do you mean by "will not go through the cylinder throats"? Do you mean the loaded cartridges do not fit in the chambers or loose bullets will not drop through the chamber throats? Or, do you mean the jackets are torn loose from the lead core when the cartridges are fired?

" loose bullets will not drop through the chamber throats"....

I cannot force loose bullets (Hornady 125 XTP, Speer 135 Gold Dot HP Short Barrel, or Ranier 130 plated) through the cylinder throats with a dowel and hand pressure--all 5. Commercial full-metal jacketed training rounds (American Eagle 130 gr FMJ) will "chamber" and shoot.

I have a M-36 J frame S&W .38 and tried several loose bullets in some of the chambers. A Hornady lead hollow base wadcutter pushes through fairly easily. A Rainier plated bullet goes through with a bit of a tap. A cast and lubed lead SWC had to be tapped through with several good taps. A Hi-Tek coated lead SWC had to be whacked on a couple of times to make it through. I am the original owner of this pistol, purchased in the mid 1980s. I'm guessing I have fired maybe 500 rounds through it - not a whole lot at all. I wish I had other examples of plated and jacketed bullets to test, but I suspect that your throats are fine. As an afterthought, I also tried this with a S&W .44 using both a Hi-Tek coated lead SWC and a Hornady XTP. I had to tap both of them rather firmly using a dowel rod and a hammer to get a pass through.

The old girl.

https://imgur.com/a/yB0ddJq[/img]

I just received a 0.356 pin gauge and it will not fit in any of the 5 cylinder throats. WTF?

I have a 3" M60 from the 80's that also won't let jacketed .357" bullets drop through the throats. The few .355/.356" bullets that I have experimented with didn't shoot very accurately. I personally don't think you will harm your revolver with .357" jacketed bullets loaded to reasonable pressures as that is what it was made for.

Having said that though, swaged or cast bullets should be easier on the old girl, and shooting slightly over size lead bullets is not going to stress anything.

I would enjoy shooting the gun, keep any +P loads to a minimum, and not worry too much about it.

Thanks for the comments. Cast is the plan for recreational shooting, can size as needed. I carry a much newer 638 (that has .357 throats) with 135 gr Gold Dot short barrel ammo...the old Model 36 stays home.

This thread got me very curious as to the throats on several of my revolvers. I managed to acquire the use of several pin gauges and did some measuring this evening. My .38 Spl S&W M-36 all throats measured .357". My .38 Spl Taurus all throats measured .357". My .357 Mag S&W M-19 all throats measured .357. However, my .38 Spl Charter Arms Undercover all throats measured greater than .359" (the largest pin gauge that I had). I suspect they would have measured at .360".

So....based on my findings and the information from others on this thread, I suggest that you take it to a competent gunsmith that is knowledgeable and experienced with chamber reaming and and get that addressed. If a .356 gauge will not fit, something is wrong. You might want to give S&W a phone call. They may cover this under warranty.

Thanks for the info Henryseale, I will call S & W tomorrow.

Simple solution for determining throat diameter(s): get a handful of lead bullets that are too large and drift them through the throats, then mic them. Once you know the true diameters you can take it from there what to do.

If they're grossly undersize it's then time to line up a competent gunsmith or machinist and have the throats reamed to common size, .356-.357.

I would just send it to get the cylinders honed either to .357 if you will only shoot jacketed or to .358 if you will shoot lead as well. Easier and will get a better result than sending it to S&W. Send it to Doug at Cylinderhone. He will do it to whatever size you want, within reason. He's done nearly a dozen for me.

PA Bob, let us know how everything turns out. My M60 also has a bit of constriction where the barrel is screwed into the frame. I don't have pin gages to measure this, but can see it after cleaning the barrel up to a shine and looking through it with the naked eye.

Even with the tight throats and barrel constriction though, it shoots really well with commercial cast bullet, and jacketed hand loads. In fact, it will out shoot a 5.5" 45 convertible Ruger Blackhawk I've owned and tinkered with for several years now. (Which is another story and on going pain in my butt).

This^^^^

Very common revolver cylinder situation ( for me more so in Rugers). For cast lead bullet accuracy and reduced leading a slightly oversized bullet (.358). and accommodating cylinder dimensions as compared to bore diameter will allow the bullet to properly obturate. The last thing you want is for your cylinder to swage down your bullet so that it is undersized for the bore.

I emailed S&W customer service, asking if they would bring their product into SAAMI spec compliance. Their response:

"Dear Robert,

We would like to thank you for your e-mail and contacting Smith & Wesson / Thompson Center.

Your firearm was produced 1955-1957. This revolver is a bit older than we would normally work on. You will need to find a local gunsmith for assistance."

OK, I get that.

Not sure what the effect on chamber/cylinder pressure is with the miniature throats. It is not a +P revolver and I do not use +P commercial ammo in it. I am seriously considering the cylinder honing option...have heard nothing but good about Doug at Cylinderhone. Thanks all for the comments and suggestions.