You’ve seen the pictures, and maybe if you’re lucky, even handled one. A fully ambidextrous battle rifle chambered in .308 that weighs in at 8.5lbs? Yes, and it shoots like a dream as well. I am talking about the Si-Defense SI-D Ambi .308. Based out of Kalispell, MT, SI-Defense is poised to take the AR-10 market by storm with this new concept rifle that will hit the market soon.