It's not bogus but it is a bit mysterious.
Many people thought the secondary pressure spike near the muzzle
that can be created under certain conditions was nonsense too... until one man figured out how to reproduce it, and blow the end off rifle barrels.
I suspect that SEE with really low charges is a similar phenomenon. The bullet begins to accelerate but pressure drops rapidly and the bullet's acceleration (not necessarily speed) drops off. The shockwave catches up and a localized ultra-high pressure event is triggered, which propagates through the remaining powder and "BOOM!" It just happens very close to the chamber instead of at the far end of the barrel.
I have no evidence to back it up, but it makes sense in my little brain.
Still happily answering to the call-sign Peetza.
You do not HAVE a soul. You ARE a soul. You HAVE a body.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.
Last edited by Brian Pfleuger; November 20, 2012 at 02:13 PM.