Man....
I've got one of those same exact open tops (in .45LC) and it's a beauty. These are all CNC produced and ought to be as lined up and reliable as any factory revolver built. And yes, there are occasional examples of other revolvers that aren't perfect, but still... it's damned rare. They are all proof fired and pass QC before being stamped and shipped, and it's VERY VERY unlikely that there was anything wrong with it to start with.
Now:
"Something" went wrong with the pressure, that's for sure. To do that damage, it was not just "high", it was off the scale. As in 200% or more of the normal SAAMI pressures it was designed to accept. Proof loads are FAR over normal spec and these shoot those without hesitation when being proofed. To reinterate: It was off the scale.
There's really only one way that happens: An overload of fast burning powder, or a detonation rather than controlled burn of a propellent due to some other variable as yet undetermined.
So:
Are you SURE that you loaded Pyrodex and not another smokeless that was on your bench? ABSOLUTELY sure? No Bullseye around? If you even own a can of another powder... well... you probably loaded it. Pull the other unfired cartridges and see what's in there. If not, where did the Pyrodex come from? New sealed can? An old one you've had for years or one gotten from a friend who had it laying around (and that's inadvertantly had a handful of 2400 dumped into it after another reloading session years ago?)
In my humble opinion as a reloader for 30+ years and as a shooter of these things, it's VERY VERY unlikely that Pyrodex would act like this. It's VERY likely that it was loaded with an overload of smokeless. But who knows...
Noting the following: There is *no reason* to load for these with Pyrodex. They are designed and specified for use with SAAMI standard pressure smokeless loads. My suggestion is to either LOAD THEM WITH STANDARD SMOKELESS using appropriate loadings, or if you want to load them "for smoke" to load them with BLACK POWDER. Pyrodex is a mule, neither horse nor donkey. I'd never load metallic cartridges for anything specified for smokeless with it. In fact, I'd never load cartridges with it for anything.
Still, Pyrodex ought not behave like this, and I suspect it didn't because it probably wasn't.
Willie
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