Just experimenting with guns on a light BA and came up with this. Outguns most medium BA!
Gangsta light assault suit
IS light BA 100 kg
3 jump MP 75 kg
2 armored gloves 0 kg
5 points basic stealth armor 275 kg 3 slots
MRR RA 250 kg 2 slots
David LGR LA 100 kg 1 slot
Of course you need to be really careful about avoiding return fire, but it does have some stealth bonuses to help out.