A gunsmith received this bolt action .243 Win rifle that suffered a catastrophic malfunction due to a barrel obstruction. The apparent offending agent? A cleaning patch left in the firearm. I don’t know where the patch was left, in the barrel or the actual chamber. But either way, a simple patch appears to have done some absolutely devastating work to the action of this rifle. Or on the other hand, the owner was too embarrassed to say what was really the cause of the obstruction, and simply stated it as a cleaning patch. Whether true or not, that rifle would serve as an excellent fence post from now on.
As to the barrel being separated from the threads of the receiver, I’m not entirely sure what transpired. It appears that the barrel itself “jumped” the threads within the receiver. However it looks too clean and undisturbed for this to have happened. Instead, I think the gunsmith who examined the rifle pulled the barrel off, to get a better idea of what happened.
In addition, notice that the explosion seems to have been on the opposite side of the pressure hole that is drilled into many civilian bolt action rifles, this one on the left side. The purpose of this hole is supposed to direct pressure away from the chamber. So situations like this are at least somewhat avoided.