Heavy loads may crack frames, split forcing cones etc, but a blown in half cylinder with the top strap bowed.............that says a reloading oops to me.
No.
The oops was done by the idiot who chambered a Single Action Army for the 44 Magnum cartridge.
Aside from a couple of prototype New Frontiers, Colt never chambered the Single Action Army for 44 Magnum. Never, and for good reason.
SAAMI Max pressure for the 44 Special is 15,500 PSI. SAAMI Max pressure for the 44 Magnum is 36,000 PSI. SAAMI Max pressure for 45 Colt is 14,000 PSI. I know there are folks who believe the SAA is good to 45 ACP pressure of 21,000 PSI, but that is beside the point. The bolt cuts on a SAA cylinder will not tolerate 36,000 PSI. It would not have taken too many standard 44 Mag loads up over 30,000 PSI to result in the catastrophic failure evident with this cylinder. It is a classic example of a cylinder letting go. First the thin bit of metal between the bolt cuts and the underlying chamber lets go, then the fracture propagates lengthwise along the chamber, splitting the chamber down the middle. Next, the the chamber walls of the two adjoining chambers fold, and finally two chunks of steel are blasted off the cylinder, either taking the top strap with them, or distending it exactly as you see here. Even with a 44 Special cylinder with slightly more metal between the bottom of the bolt cuts and the underlying chamber than a 45 Colt, the cylinder just could not take pressures up to 44 Magnum levels.
I found the ad on Gun Broker. The SN of the gun indicates it was made in 1960. Well into 2nd Gen production. Standard calibers for the 2nd Gen were 357 Magnum, 38 Special, 44 Special, and 45 Colt. So it is logical to assume that a 44 Special SAA was modified to accept the 44 Mag cartridge by lengthening the chambers slightly to accept the longer 44 Mag cartridge. The 44 Special barrel could have been used as is. The MAGNUM marking on the barrel was obviously done at a later time. Even if the conversion had been done to a 357 Mag or 38 Special SAA, the result would have been the same.
Years ago I used to buy my bullets from a local bullet caster. He had an exploded cylinder from a SAA he was using as a pencil holder. It was exactly as I described, with three chambers daylighted. I asked him the story. It seems that one of his customers bragged he was going to experiment hot loading 45 Colt ammo to 44 Mag pressures. The bullet caster made the guy promise that when he blew up the gun, he would give the cylinder to the caster as a memento. That is exactly what happened. Obviously, a 45 Colt SAA cylinder cannot take 44 Mag pressures. Neither can a 44 Special cylinder that has been modified to accept 44 Magnum rounds.
There is a good reason why the 44 Magnum case is about 1/10" longer than the 44 Special case. So bonehead disasters like this do not happen.
