I am the first one to get irritated at selfish heavy ammo takers; BUT INFERNO is a whole other ballgame. Yesterday, I played inferno Clash for the first time and heres how Heavy ammo went: 1) first time, I go there to lock it down and end up killed by two opponents, while I waited for allies 2) second time, I go there to lock it down and get shot gunned by an opponent that came up from an unseen direction. 3) third time, two other smart people joined me where the box spawns before it actually did, we waited a couple seconds for a fourth, then cracked it open. 4) fourth time, I see a few allies nearby so I go to the box and wait 5 seconds, only to see everyone disperse. So I turn to face the box, wait a couple more seconds then open it. A (bitter heavy-ammo-less team-mate runs up to my face and starts meleeing me with rage; because of him I don't see an opponent come out and kill both of us, now their whole team has heavy and none of ours do, we go from a lead to losing. So, As far as I can tell, you don't wait more than a couple seconds for allies to join you at the Heavy Ammo box; its incumbent on everyone to head over there quick, when the "incoming announcement" is made. Obviously this is a bit map-dependent because there are some maps which have the heavy in a safe spot.