Assuming you have a complete .223 already that you will scounge from.
You would need
(prices are for the stuff I would get)
RRA Upper - 440 (A4 with Carbine FF HG)
RRA Mag Block - 119
RRA Hammer - 15
Buffer - 24
Colt Mag - 60
And thats it right? Assuming you have a CAR Stock? Also this would be really close to what Colt sells correct?
The hammer is *optional* IF you have a compatible 223 hammer. Look at the frequently asked questions that is tacked about 9mm to see pics on the hammers.
You can hold off on the buffer for some time. I have a 223 buffer in my 9mm and it's running fine so far....
Colt mag, sorry. I would rather buy 2 generic mags then a Colt for that price. (I don't care about the hold open feature).
Or just an Oly upper that will sit on any 5.56 lower without modification. With a $65 mag block you can use $5 each sten mags. Thats twelve for the price of one Colt mag. (I can divide fast too). Somebody may hate on my post cuz they don't like Oly but just giving you some options.
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