My go-to rule with attack rolls is whoever wins hurts the other. This goes even with ranged attacks. Two gunslingers fire at each other, whoever wins hits the other.
The only time a ranged attack wouldn't risk a counter-attack is when the defender doesn't have a ranged weapon to defend with.
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I have already solved this problem. When making a ranged attack, the attacker rolls as normal. At the same time, the target has 6 + their Skill as a target number. If the attacker rolls equal to or higher than the target number, the attack is successful. If lower then the attack misses. This way, ranged combat goes faster.
While 6 is an ideal number so that you hit more often than not especially when facing hordes of xenomorph-like monsters, GM can change that to 7, 8 or even 5 to increase the difficulty or lower it.