Jeff Siewert

So we had a pretty good handle on, even though the velocities were high, we had a pretty good handle on what the actual velocities were.

That conograph had to have a pretty fast clock in it.

of course this was 40 years ago yeah anyway all right let's go on to the next slide so this is um this is what happens when you fire a um 9x19 cartridge in a 357 sig and you can see the thing looks like a pregnant guppy and sad to say i was the one i was the culprit that was involved with this and we were at the range with some friends and um

And like, oh, well, damn, it won't fire again.

Like, what the hell's going on?

And, you know, you give the sliding ink and it won't move.

So after a little bit, we did get it to move.

But, yeah, so the residual stresses were pretty high.

And I was actually very impressed that the cartridge cases didn't rupture.

Okay.

Well, I wish I could take credit for having done this as an experiment, but there was no intention there, unfortunately.

Okay.

So folks talk about annealing all the time.

And the thing I always worry about is this hardness profile.

So for all brass cartridge cases, there is a hardness profile as you go from the back end to the case mount.

And in the upper left-hand side, you see the cartridge case hardness profile, the upper and lower boundaries.

And you're cautioned, if you look at the cartridge case drawing,

You're cautioned that you dare not have a sharp discontinuity in the hardness profile.

And the red line there, the red dots with the red line show you a hardness profile.

that met the boundaries of the drawing, but the gradient was too steep, you know, kind of, let's just say a few tenths of an inch back of the base of the shoulder.