The increase in price for the mac guns is because of the .556, 7.62x39 and other caliber uppers that are pending tech branch approval for them. There are currently 3 different companies who are in various stages of approval.
So, Mac's have basically taken a huge prince increase due to basically being treated like an auto sear.
Since they're already treated as machine guns, the upper is basically nothing more than a quick caliber change is all.
This^^^^^^^^^...


