The following explosive models have no/incorrect collision data.
- IED_LAND_BIG
- IED_LAND_SMALL
- IED_URBAN_BIG
- IED_URBAN_SMALL
This means...
a) You cannot shoot them and trigger them, the bullets go straight through into the ground
b) They do not get set off by other explosions, so IEDs can survive anything unless they are manually detonated with 'setDamage 1'