Back in the day, Ive used both an AK 762x39 and the old m-15/16 223 or whatever you want to call it they do change every year it seems, now its the good ol M-4, although I liked the acuracy of the 16, I liked the punch of the AK...but thats just me, was that a good enough explaination for you sir?
Its no big deal, I'm sure it will be great when it is done, I've seen nothing but perfection from this detachment