Yo when a site does not get a response for a couple years it has to been pretty layed back and easy. I hope I get a response in a couple years. Here is my two cents on soft recoil for artillery.

The recoil motion is a bunch of kenitic energy. Since energy can be neither be created or distroyed it must be transfered/converted somewhere else. The recoil energy of an artillery howitzer is converted to heat. This is the same as an automoble travelling at speed (kenitic energy)coming to a stop. The energy is converted to heat (brake pads and rotors)and heat disapates into surounding air. The artillery piece's recoil drives a piston that forces oil to compress nitrogen gas producing heat. My favorite artillery piece the 75 Pack Howitzer has a supper clever way using valves and residual nitrogen gas pressure to reset the the recoil mechanism for the next shot. Not only does the recoil mechanism soften the recoil but also prevents slaming when the gun returns from recoil.

I enjoy thinking about recoil many ideas can work. I would like anyone to jump in to tell me the latest developements. Please excuse my spelling.