I've never used a sniper rifle. But now that I'm on my 3rd prestige, I have like 7+ class slots, I can dedicate one just for 'having fun/trying to quickscope', I'll primarily only use it on combat training or when the whole other team is playing a campy sniper game I'll jump in on the fun.
So what's the best sniper-rifle to use? Best perks? Attachments? Etc.