I am running darkRP for a couple years now, never had this problem and suddenly I get this:
[ERROR] gamemodes/darkrp/entities/entities/spawned_weapon/init.lua:30: attempt to perform arithmetic on local 'amount' (a nil value) 1. DecreaseAmount - gamemodes/darkrp/entities/entities/spawned_weapon/init.lua:30 2. unknown - gamemodes/darkrp/entities/entities/spawned_weapon/init.lua:82
I use M9K and fixed the ammo bug a long time ago where you make the clips the same sizes.
When you drop the gun it looks like this:
And you can pick it up as many times as you want.