Question for you S&W guys.

[cabezaverde]

I have owned a fair number of handguns in my day, but just acquired my first Smith - a 642. This is an alloy framed, stainless barrel and cylinder carry gun.

Here is my question - the throats appear to measure .356 - .3565". Is that tight for a Smith?

My standard 38 practice load is a mild one - but I size the bullets .359" for my other .38's and .357's. I really want to stick with one load for practice.

The .359 loads chamber fine in the Smith - any problem using them on a regular basis in this gun?

[Edubya]

Hey green head, can you push them through the cylinders? What BHN are you running?
I've not tried .359 through mine. I load "as cast" a WC and there might be a few .359 in the bunch, but I cast them with tape on WW and they are accurate! I can keep my rounds on an 8" plate all day at 25 yards out of my 642. The only thing that I've done to the gun is to smooth out some of the action. Well, I didn't do the work, a friend is a gunsmith and he did it. He said that it would have smoothed out by itself with about another thousand rounds through it.:)
EW

[cabezaverde]

So, I guess what I am asking is if the .003 oversized is going to be a problem.

[leftiye]

Slugga you bore! If the barrel is large enough you can open up the chamber mouths to plus .001" over groove diameter. (and shoot larger boolits - maybe the same ones that you use for the other guns). You COULD shoot the oversize boolits in your gun BUT they woulld size down in the chamber mouths - causing high (er) pressures and probly doing no good for accuracy. If they chamber at all.

[shooting on a shoestring]

How did you measure the throats? It could be there's some error in your method of measuring. I agree with Edubya, push or drive a boolit through the throats and measure the outside diameter of the boolit before and after. That will tell you pretty well if you really do have tight throats (and .356 for throats is very tight). However, if you also have a tight barrel, shouldn't be problem. But if you do have tight throats and a larger barrel, you will have leading, and accuracy troubles.

It won't be dangerous to shoot, just short on good results.

[cabezaverde]

I don't think I am communicating well.

My standard .359" 38 Special round chambers fine.
I have slugged the throats - .3565".
The gun shoots fine.

Given the alloy frame - am I going to damage the gun with light to normal .359 diameter loads?

[imashooter2]

No, you will not damage the gun with .359 diameter bullets in standard pressure loads.

[machinisttx]

You may have trouble getting .359 boolits to chamber if the seating depth puts them in the throat.

[MtGun44]

No, you will not damage the gun. It takes a trivial amount of extra force to size the
boolit down the extra .001 or .002 over what factory ammo is sized to . Think about
a jacketed .357 or .358 diameter boolit, which is just fine for this gun, would do pressure
wise, compared to a lead boolit.

Bill

[Marlin Hunter]

If you use a Lee factory crimp die, you wont be firing .359 boolits in your gun, regardless of what size they are before you put them in the cases.

[JIMinPHX]

Over the years, I've measured the throats & barrels on several S&W revolvers. They usually do a really good job of keeping the throat diameters all pretty close to the same within a given cylinder. I've seen throat to throat deviations of .0002"-.0005" on most guns that hadn't been subject to obvious abuse. Unfortunately, their matching of throat diameter to groove diameter does not tend to be so good these days.

The last S&W that I bought new, had a groove diameter that was about .003" over the size of the throats. It leaded badly. I called Smith about it. They said to send the gun back in with a letter explaining the problem. They even sent a call tag & prepaid the shipping for me. They then proceeded to hold the gun for months. After several phone calls & several stories from them that didn't really match, they sent the gun back to me with 3 dirty chambers (obviously fired) & a note saying that the gun had been inspected & was safe to fire. There was no response to my request to have a barrel with a smaller groove diameter fit to the gun, even if I had to pay for it. They paid shipping both ways. They didn't charge me a dime for anything. But they did not do what I had asked them to do.

I have a piece of barrel blank that will fit. Some day, I may get up the nerve to try to dislodge that "crush fit" hybrid barrel that they now use. Until then, I will get by using hollow based boolits for lite loads or jacketed ammo in that gun.

Most of the older Smiths that I have seen, have been fine cast boolit shooters.

If I were making boolits for a gun with a .3565" throat, I would size no larger than .357".

I tend to take it easy on alloy J-frame .38's. I would be comfortable leaning on a steel framed .357 a little harder, but the air weight .38's I treat with kid gloves. Something that is "safe" to do a limited number of times, can have a detrimental wear effect if you do it to those things too often.

Some of the air weights (like the scandiums) have limitations on the grain weight of the boolit that they are rated for. I don't know if your particular model falls into that category or not. You might want to read the owner's manual regarding approved ammo.

[S.R.Custom]

So, I guess what I am asking is if the .003 oversized is going to be a problem.

What Bill said-- no problem whatsoever.