The reason you need parental permission is because you are not legal liable as an adult until you're 18, because you're still considered a minor. So if you get hurt or do something stupid that hurts someone else-- they [your parents] will be sued because you can't be. You cannot legally enter into any contract with anyone under the age of 18.
As far as the sniper courses go:
Contact Sha-Do about the ASC Sniper courses. He's one of the people who organized the whole ASC sniper certification system.
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