Thats what i usually do in Sniping mission. BUT!...it works well on Non-moving target, like in the watchtowers. For the rest, its a bit difficult, specially on night missions in which u cant see well. Most of the time i just snipe the guy in watchtower with sniper rifle, and if they try to look for me, i usually hide or ambush them.
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*GEL*DeathStrike[gm]
Gods Elite Legion
www.godselitelegion.s5.com