Portable air compressor + projectile launch mechanism would create a weapon that doesn't need bullets / gunpowder or even steel casings but could function just by utilizing the environment (rocks, small solids) and fire them like a pistol would. The range would probably be lower than a regular pistol using gunpowder cartridges but it could be just as lethal. As lethal as shrapnel.
The weapon in question would operate on electricity.
In other words - a portable chicken gun.