I have been unloading my inlines, cap locks and flintlocks with compressed air for years. I use an off-the-shelf small chuck over the nipples of the cap locks and another chuck with a small 4 inch long tube for unloading the flintlocks. No need to disassemble any guns except for T/C Scouts. My compressor is set at about 100psi. I put the muzzle in a clean plastic bucket and recover the slug and most of the powder.
