[Johnny got his gun]

They drop like normal CS weapons. I send "drop weapon_glock18" etc, so they are dropped just as if you would be fast enough to drop them when you die.. which really is impossible...
So yes if you had a primary weapon, the secondary weapon would end up at the same spot on the ground so if you're not aware of it you might not notice the 2nd weapon until you pick the big weapon up etc :-)

I dont think it can drop multiple primaries :-\ not sure how CS works there...