Loads like a SAA Colt but underlever rotates and cocks it. Blow-by is negligible, hardly noticeable with normal shirt sleeve.

Opened for some still shots, at top of the inside pix screwed in is the firing pin, impact type with return spring. The ratchet or star with the hand is visible below on the left side, also the pawl that cocks the hammer. The cylinder indexing lock is external, operated by the under lever. At very bottom the small knob releases the cylinder to turn clockwise for loading.

Due to limited equipment I was unable to copy existing mechanisms so it is pretty much designed from scratch, largely by cut and try, trial and error, etc.