Extraction problem with 340PD

[westernrover]

I just bought a new 340PD. I shot a little more than a box of .357 ammo the first day. The extraction was very hard. A couple times, the cylinder slid back when I was pressing on the extractor rod. I had to use a squib rod to knock the cases out.

I cleaned it very well with Breakfree CLP, brushes, patches, bore snake, and wiped it dry. I took it out again to check a few things. First, was it just one chamber sticking? Second, would nickel-plated cartridges extract better? For the first 20 rounds of brass cartridges, it extracted fine. Then they started to stick. I marked sticking cylinders with a Sharpie but ended up with at least four marked after 25 rounds. The cylinder was sliding back again and some brass broke inside the cylinder. The nickel-plated cases were sticking also. All of this ammo goes into the 340PD cylinder without any trouble. It drops right in. The same ammo also fires and extracts from a 640 with no issues.

What's going on here?

 

[ArchAngelCD]

The cylinder should not be able to slide back. That revolvers broken, STOP firing it!

Are these reloads? If yes what is the recipe, everything in the recipe. Brass, powder, powder charge, primer, bullet and trim length. Darned if those done look like over pressure loads.

As for firing fine in your M640, that is an all steel revolver, not an AirLite. S&W recommends against shooting light bullets in an AirLite revolver.

 

[243winxb]

Looks like hot handloads in old tired brass causing the sticking and case separations. Old brass doesnt spring back after firing like new brass. Harder nickel brass sticks sooner.

Cylinders expand when the rounds are fired. Titanium has to be different then a steel cylinder.

The use of the range rod to beat brass out of the cylinder may have bent something?
There is a stop that restricts rearward movement of the cylinder when its in the open possition. The stop is a nub (protuberance) on the frame. Check it for damage.

This is my guess without knowing all the facts.. Factory ammo or reloads??

 

[gotboostvr]

It should be impossible for the cylinder to move like that in a normal functioning revolver.

I'd guess the ammo is causing the extraction, but something else is causing the cylinder to behave like that.

If that was mine, it'd be in a box on its way to S&W.

 

[Pat Riot]

I would be calling S&W for repair. The cylinder shouldn’t be moving. It could also be the chambers weren’t polished.

 

[Waveski]

Your Smith&Wesson is exhibiting multiple malfunctions. One may be the fault of the ammo ; you need to share info on just what that ammo is. The cylinder movement is a mechanical failure. A clear image of the cylinder stop - the "nub" referred to by 243winxb - would be interesting to see.

Send it back. S&W is backlogged badly with recalls , and those get first priority. Do not expect a quick turnaround.

 

[Walkalong]

Rough chambers? Factory ammo?

 

[243winxb]

Rough chamber

Very possible if factory ammo.

 

[labnoti]

The brass case has to slide back and hit the recoil shield upon ignition. A titanium cylinder has higher static friction than stainless steel. The material is known for fretting and galling. If the pressure of combustion and the friction of the brass on titanium is holding the case against the chamber walls so that it does not slide, the pressure against the back of the case will stretch the case until the stretching is stopped by the recoil shield. If it stretches it enough, the case will pop in two.

 

[Walkalong]

Interesting, and all the more reason for nicely polished chambers.