[JLStorm]

I know this is a stupid question, and I know I have heard answers to similar questions before which I cant recall...but what is the reason the bullet weight must be at least 120 grains for the S&W 340PD? I understand minimum powder requirements due to under pressurized rounds...but bullet weight I cannot recall.

BTW, this is printed very noticeably under the barrel of the 340PD.

[Ben Shepherd]

Not familiar with smiths but: This is an ultralight 357, correct?

If so, it most likely has do do with bullet pull under recoil. It takes a heavier slug to have enough physical length to have enough bullet pull so it doesn't pull out under recoil.

[jamz]

It has to do with unburned powder burning a cut across the top strap of the gun with smaller bullets.

As I understand it, it's best if most of the powder burns before the bullet exits the forcing cone, so the gas doesn't damage the top strap. The heavier the bullet is, the longer it is, the more time it takes to travel along, and the more it will "block" the gas until it is mostly burned away.

I also hear on the internet (so it must be true) that it only applies with .357 loads, not .38 special, so you can use whatever bullet weight you like with the .38s.

It actually does not have anything to do with bullet pull, that's independent of the weight. In fact, one would surmise that under identical crimping conditions, heavier bullets would actually pull more. In the manual, Smith mentions that you want to test any carry load for bullet pull under recoil. I've found that Speer GD 125 grain bullets pull a tiny bit, Speer GD 135 grain don't pull at all, but cheapie 158 grains pull a ton- enough to stop the gun.

[GunNut]

jamz is the man and has the answer correct.

Steve

[norfdet893]

I had heard that it was due to rounds coming loose during recoil jamming up the cylinder. I had not heard of powder burns being a problem. I previously owned a 340PD and sold it becasue it was most unpleasant to shoot with magnum loads. I replaced it with a Smith airweight with +p loads. YMMV

[JLStorm]

thanks guys :D