Ok, you people need to know about something I first read about in a gunrag.
'Scalled "Bugshot".
1.) Start with a STAINLESS .22, or you have to be religious about cleaning.
2.) SAFETY GLASSES. This is STUPID. (But it works.)
Pull bullets on some .22 rimfires. save powder and set aside. Brand matters, I had old Federal .22 Longs that worked, but Remington Thunderbolts didn't.
Take a spent case, cut it off, and file down to about 1/8" OAL. Stick it to a small stick. This is your powder dipper.
Take an empty, unfired case, and charge it it with one scoop of saved powder. Top with a tight-fitting card wad. Something a bit thicker than heavy tagboard. Didn't think of wax here when I did it.
STUPID PART: pack it down tight. I used a bamboo skewer. In a LIVE rimfire case. I said it was STUPID, but I never set one off. Naytheless, I never looked down on it either. Kept all parts of my anatomy well out of alignment with the open end whilst packing in. It seemed neccessary, as un-packed loads failed to ignite the powder charge.
Fill case with coarsest available table salt. Top with another cardwad. Done.
Out of a single shot rifle, these went off quieter than a capgun. Kind of a cross between a "Thwack!" and a "Splat!". Pattern at across-the-room range was about 8", with dispersion space of about 3/8" between crystals, quite even. Penetration at same range was handily through a piece of notebook paper. Closer range made smaller, ragged holes and a puff of paper dust.
These things are DEVASTATING on wasps. Crystals typically penetrate completely, with no damage to paint or walls provided you don't shoot directly at the surface at close range. Mosquito Hawks at 6-ish feet were smashed, with broken legs, oozing bodies and perforated wings. It didn't splatter the bugs unless you were too close, in which case it'd be like swatting a dove with a full-choked 12-guage load of birdshot at minimal range.
I had so much fun with these I ran out of targets. The neighbors knew nothing. Salt sweeps up easily, but it rusts guns FAST. (Hence the stainless advisory.) Houseplants don't like it much either, so rinse 'em off or find little dead spots on leaves later.
I first read about these in the context of a guy who was shooting mosquitoes with his Ruger Mk II on a boat. His buddy's anti-gun girlfriend had IMMENSE fun stalking mosquitoes all over the boat for the whole night once she saw what was going on. Result: one ex-antigunner, numerous vaporized mosquitoes.
The hard part is developing a load that insures consistent powder ignition. Thunderbolts WOULD NOT ignite the powder, no matter what I tried. Primer-only power in rimfires is too weak to shove a salt-collumn fast enough to do anything other than dribble out of the barrel, hence the neccessity of the stupid bit above..
I haven't tried this with centerfires, but it oughta work, probably with primers only. You'd just need to dial the shotload to where it'd work well, and an entire centerfire case fulla salt might be a bit much. Handgun or rifle probably won't make a whole lot of difference either.
Sugar instead of salt might work also, as a non-corrosive alternative. Dunno if I'd want to be sweet on roaches, though.
Remember, I said it was STUPID to reload rimfires like this. It's probably quite dangerous. It merits further investigation and research, particularly on the centerfire applications.
As an addtional point of stupidity, this is the only reloading I've ever done. Using a different type of powder than what I pulled from the rounds might work better, but I didn't have any variety at the time. All the same, I used up 5-6 boxes of old Federal .22 Longs that I got from my grandmother after my grandfather died.
But beware. It's addictingly fun.