With a quick tug, the cord loosed the hammer, the firing pin being driven forwards to strike the primer of the shell and start the cordite explosion in the breech. Just as the shell was being forced forwards out the muzzle, so too was the barrel being forced back, the piston running parallel underneath it starting to force against the hydraulic fluid inside it, the fluid in turn compressing air in a separate chamber of the gun. The 25-pound shell left the barrel with a resounding crack and small flash of flame, a smoky plume erupting out of the muzzle as the round flew true. In all, the carriage of the gun hardly moved an inch, and the barrel was already starting to return back to it's firing position as the compressed air pushed back against the hydraulic fluid. Pressure Cooker would definitely be happy that that part worked.
The ringing in the pegasus' ears subsided fast enough, a wide grin across his muzzle as he spread his wings and took to the air in celebration, kicking his hooves about in the air giddily. He caught his celebrations short, however, turning back to look at the impact zone — well, firing is only half the fun, gotta see where she lands! Half a second later, a small flash erupted from beside the tree he had aimed towards, signalling a successful detonation, and past that a very well-aimed shot. Though, as the flash faded, and something now much larger than the tree caught his attention… perhaps that shot was a bit too well-aimed.