Lunar COTS Launcher

120mm tank smothbore firing 12kg (8kg of which is propellant) shell at 1000m/sec in vacuum (chamber pressure around 5800 or so at detonation)

stage 2 propelled from initial charge with Mk66 mod6 (Hydra 70 missile) motor charge at 1000m/sec (5kg)

I haven't done my math completely, but if the MK66 and the associated electronics survived the cannon launch, it would make a VERY handy way to launch small payloads to lunar escape velocities barring the development of some sort of railgun (which is probably far more likely, anyway).


Still, small solar-sailing microprobes could be launched across the solarsystem this way, or, if it were economical, H3 bearing regolith back to earth or earth-oribital processing facilities. Impact vibration of the cannon would stir up dust which would be harmful to the operation of the cannon, so it would need to be protected by some sort of curtain or screen within seconds after firing.