As for a good template, try Da Frontline Trooper's. He has made a lot of Youtube videos of his weapons and he publishes his blueprints on his facebook. That's the best I can do for youSure thing I'll check it out, and thanks for the advice, I think I'll mold or pep my helmet and use foam for the rest then.
Thanks again.
Also, I forgot to ask, where can one find the lightrifle template you're using?

You can also check out this thread http://www.405th.com/showthread.php/39765-Halo-4-Weapon-Blueprints