The scandium 340: 38 wadcutter loads

[American1776]

A very experienced gunsmith that I personally corresponded with told me that a K-frame model 10, shot with target wadcutters, should hold up for approximately 100,000 rounds before endshake and timing go out of spec, and possible need of a re-build. That sounds reasonable.

Considering the new metallurgy and scandium laced aluminum that can withstand 357 magnum, how should we translate the round count lifespan of an M&P 340 with wadcutter / target 38 special loads?

This might be theoretical; but these guns have been around now for a long time. Has anyone shot a scandium J-frame with *just* standard 38 spl for many rounds? I know the whole "your hand would give out before the gun" trope with the magnums. I'm just interested in treating the 340 guns as just 38s.

Thanks.

 

[s&wchad]

I can't help with the 340PD. I've only fired mine on one occasion an don't carry it.

I can offer a little insight on the 342Ti. I've carried and shot mine since 2001. I only use jacketed bullets, because of the cleaning protocol for the titanium cylinder. I don't have a round count, but it's probably around 2000. The majority were standard velocity range loads and the rest were a mix of standard and +P defensive ammo.

I had to send the gun in for service 2 or 3 years ago. It had a bit of endshake and the cylinder was jumping the stop lug while extracting fired cases. S&W straightened and stretched the yoke barrel and had it back in my hands in about 3 weeks. The work was covered under the lifetime service policy.

 

[American1776]

I can't help with the 340PD. I've only fired mine on one occasion an don't carry it.

I can offer a little insight on the 342Ti. I've carried and shot mine since 2001. I only use jacketed bullets, because of the cleaning protocol for the titanium cylinder. I don't have a round count, but it's probably around 2000. The majority were standard velocity range loads and the rest were a mix of standard and +P defensive ammo.

I had to send the gun in for service 2 or 3 years ago. It had a bit of endshake and the cylinder was jumping the stop lug while extracting fired cases. S&W straightened and stretched the yoke barrel and had it back in my hands in about 3 weeks. The work was covered under the lifetime service policy.

thanks for sharing that info.

Glad you got it addressed. I've been concerned about the cylinder jumping the stop lug while extracting cases. There is so little material on the frame that contacts the cylinder. If one pulls the cylinder outward just a little bit, and then pull back, it will jump the frame.

How did S&W address the frame?

Seems like this is just a peculiarity to the lightweight revolvers.

Do the airweights (638,642, etc) have this issue as well?

 

[s&wchad]

There was a document returned with the gun that stated they straightened the yoke. They don't provide a lot of information. That tightened things up enough that it doesn't jump the lug any more.

I have several Airweight and Airlite revolvers and they all have very little engagement between the cylinder and integral lug. I don't know why they didn't make it taller on carry guns. I have a couple 317's (.22 LR) and the lug is a lot taller on those.

 

[Marshal Tom]

This happened to me several years ago with an Airlite Ti. I sent it in and was told it could not be fixed. They gave me a choice of guns and I took the M&P 340 that I have now. I have not had it happen with the 340 yet.

 

[American1776]

There was a document returned with the gun that stated they straightened the yoke. They don't provide a lot of information. That tightened things up enough that it doesn't jump the lug any more.

I have several Airweight and Airlite revolvers and they all have very little engagement between the cylinder and integral lug. I don't know why they didn't make it taller on carry guns. I have a couple 317's (.22 LR) and the lug is a lot taller on those.

If you load some cartridges into the .38/.357 light weight guns, you'll see how far the rims extend out toward the edge of the cylinder. There's very little space! That frame stop has very little room on the cylinder when there are cartridges extending almost all the way out to the edge of the cylinder. If they made the frame lug engage anymore into the cylinder, it would interfere with the cartridges.

I think that part is hand filed by a craftsman at the factory to fit just right onto the cylinder without hitting a cartridge rim.

 

[s&wchad]

Good point, I never considered that. No wonder they made the 317 lugs a lot taller!