[CLOSED PR] Kinetics improvements & magazines

[Tarmunora]

Mmm, overall I don't personally see the need to de-abstract this - while the current implementation is, well, abstract and gamey, this is a video game (and even most shooters treat ammunition as just an invisible bucket of bullets that you shopvac out of corpses) and imo we're not really a game about guns to the extent that justifies realistic magazine handling etc.