Given that Pulp knows some folks in common with the guy I would say that we have to take these pictures as related to the guy's story for now until proven otherwise.
And I gotta agree with the others that there's far more to the story than what the guy said while in shock.
First off why in blazes would someone clean their rifle then put some BP into the bore along with a cap to "flash" the gun? Seems like the powder would then require that it be cleaned all over again. Or could he have tried to clear a dry ball and picked up the wrong powder and got more into the chamber than he bargained for?
On a related note and just to cement the need to double and triple check the powders being used there was a fellow up this way that suffered a blown up gun, VERY serious injuries and from what I've heard the loss of his right eye. He was loading some handgun rounds then switched the machine over to rifle. Well, I guess you can imagine what he forgot to do, right? Near as anyone can tell he loaded up the rifle rounds with handgun powder.
Surprisingly enough the Remington 700 didn't blow up on the FIRST shot. There was a helluva BANG! that startled everyone but since they didn't know what sort of rounds he was shooting no one thought to stop him before he chambered the next and pulled the trigger. The lugs on the bolt snapped off, the receiver split into three parts and generally the whole middle of the gun became a pipe bomb. The bolt shot directly back and pulverized his eye and other lacerations and injuries were done generally to his upper body. But the eye and forehead were the key ones.
So just be doubly sure that you KNOW what powder is going into what casings or into flasks and the like. It's simply too easy to mess up if our minds are not on the task.
For my part during reloading the powder jar sits at the loader and on top of that when I've filled the hopper and graduated the powder drop a bit of masking tape with the powder and charge is put right on the hopper. It takes a few seconds and for the most part seems like a waste of time. But if doing so can jog my memory at some point in the future then all these added time wasters are worth the few moments.