Yep, you need one. I would go with the studs and do it right. The best sling I have found is "The Claw" by Quake Industries. They don't slip and don't allow the gun to bounce. The swivels that come with them are junk - best to replace with Uncle Mikes. I have this sling on all our rifles too. They come in camo, green and black.
Good hunting!