Thursday, October 29, 2009

So What Happened?

ASM826 ya got me going.

Smiths' and Colts' cylinders rotate in opposite directions. Holding the revolver pointing away from you, Smiths rotate counterclockwise (I checked my mod 22 just to be sure).
That means that in the rotation sequence of the cylinder, the previous cylinder never was fired. The jacketed projectile is still in the cylinder while the cartridge next in line to be fired is missing the projectile. The chamber in which the bullet was fired has been blown completely out of the cylinder.

Curious.

Now look at the exploded chamber without a projectile sticking out the end; the edges of the casing are bent out. This indicates that the cartridge had powder in it that exploded. This (plus the projectile lodged in the remains of the chamber) means that there was NO projectile previously fired that could have blocked the barrel and that whatever the cause of this catastrophic failure, it was founded in the top center chamber alone.
There were actually four photos in the email I got from Al and I did not include this one since it was so similar to the other. But I see now that I posted the wrong photo since this one shows the forcing cone of the barrel as well as the cylinder walls. The other photo didn't. My apologies.

Look at the position of the top center chamber and see how it appears to be out of alignment with the forcing cone. I thought perhaps it may be that whoever loaded the weapon did not allow the chamber to "index" properly; that is the firing chamber and the barrel must be perfectly aligned in order for the projectile to enter the barrel properly and allow the rapidly burning/expanding gases to vent quickly. The cylinder stop tab usually accomplishes this purpose.

If the firearm was operating properly I don't see how this could happen. The internal mechanism of the revolver works to prevent any misalignment. As the trigger is pulled (double action) the cylinder is rotated and locked in alignment prior to firing. The same thing happens in single action.

Of course with wear the chamber can get slightly out of alignment with the forcing cone. There are several reasons for this. But when it happens, a small portion of the projectile may be "shaved" and ejected out the side of the weapon between the forcing cone and the cylinder.

I experienced this in the police academy when we trained on 30 year old revolvers (Colt OP's)that had a bit of "slop" in the cylinder alignment. Splinters of lead shot out of the revolver being fired in the station next to mine and embedded themselves in the back of my left hand.

It stung a bit.

From the looks of what remains of the chamber wall, this weapon was more than just a little out of alignment. Yet it does not appear to be that old.

Anyone have thoughts on this?

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