[lurkingknight]

semi auto is the hardest on a gearbox. Full auto if set up correctly really only puts strain on the gearset and piston when the gears start and when they hit the piston to grab it.

Semi auto is always starting from a dead stop to slam into the piston and then dead stop again as it finishes the cycle. The trigger contacts arc every time you pull the trigger, whereas in full auto the block arcs once as the block comes close to the contacts, but then it stays pushed in rather than ejected by the cutoff lever.

semi auto is also hardest on the battery as the startup to get the gears moving requires more current than it does to keep it constantly moving, even with the slowdown when the gears pickup the piston.