Found a workaround that works based on an static object named "Bomb" as detonator, it seems to work well with any ordenance:
_dir = getDir player
_pos = [(getPos player select 0)+sin(_dir)*200,(getPos player select 1)+cos(_dir)*200, 50]
_b2 = "Bomb" createVehicle _pos
_b2 setPos _pos
_b1 = "M_Ch29_AT" createVehicle _pos
~0.05
deleteVehicle _b2
exit
Still 0.05 secs wait is needed before deleting the "detonator" object.