After some beer and thought...unless the safety bridge is FUBAR, the bolt was defective and the trigger group is faulty. I'd say both since the bolt had to partially be in battery for the pin to pass through the safety bridge. The pin will hit the safety bridge before the bolt turns which means the hammer had to hit the pin after the bolt had it indexed for the bridge. Since the bolt lugs were mostly engaged, the metal from recycled soup cans that the Chinese used for the bolt failed. The hammer released from the sear without using the trigger causing all of this.
That's my story and I'm sticking to it.