Cheyenne,
Understand that the full price is for both guns and accessories. So the DOD can buy up to the $15 mil limit on any item specifically listed in the contract. Often that includes suppressors, spare magazines, sometimes optics, etc. So you can't just divide and get a per-unit price, because we don't know specifically what they will buy with that contract. We know some of the models, and some of the items, but we don't know how many of which items they will be buying.
