Allegedly owned by someone that attended the DEFCON Shoot event where gun powder was transferred to the package, tipping a dog doing a random search in the Forums.
That would be wild. Bomb dogs usually are not trained to hit on ammunition since every officer on a scene is carrying some. Gunpowder is also a low explosive (meaning it burns at subsonic speed) which sucks for making things go boom.
Yes, but a lot of modern formulations are based around RDX chemistry or nitroguanidine, etc. So, a big portion of the "smell" is high explosive even if the overall formulation burns subsonic.