[FMA] Armour

The other radical idea I've had is this concept:

Armour protects against small arms, side arms and fragments, but is penetrated
by long arms or rifles.

Powered Armour is immune to small arms, side arms and fragments, protects
against long arms or rifles, but is penetrated by MG, HMG and cannon fire.

Long arms, rifles are battle range or line of sight, while small arms, side
arms, fragments have a range that is measured.

I haven't figured out adequate FMA mechanism's to do this yet.