I'm with the guys raising the B.S. flag with regards to blowing up vacuum cleaners. First, how can a primer ignite with its anvil unsupported? Second, even if it detonate a primer, the volume of innards of a vacuum is WAY too large to contain an explosion unless you sucked up a copious amount of powder. Third, too have been doing it for a long time with no ill effects. Fourth, if I ever did it, the FIRST thing I'd do is take pictures, which no one else seems to think to do.
35W