converted 223 AR to 9mm

[Nicoman]

Im looking to convert my AR 223/5.56 to 9mm. Is it as simple as changing uppers and hammer or is there more to replace? Can I just change to a 9mm barrel and bolt and keep my upper or is this a no go. Any advice would be greatly appreciated

[Mr. Blonde]

You might as well just build a 9mm AR from scratch. I believe you need a dedicated 9mm upper receiver; its blowback operated. As for the lower, you could get a 9mm magwell block such as from Spikes Tactical to convert you 556 lower. Otherwise the are companies such as RRA or CMMG that make 9mm upper/lower receivers and complete rifles.

[jaustin612]

You'll need a new upper, just get a complete one, I picked mine up from cmmg, its good stuff. Youll need a magwell adapter as well, get the hahn dedicated one, its easy to install, and is about 200 bucks off of rainierarms.com. If you go with that set up you wont have to change the trigger group at all. you'll want to get a 9mm buffer as well, as it has to be about twice as heavy as a standard ar buffer. all in all about 650-700 bucks.

[CSI304]

When I did a RRA 9mm set up:

9mm Barrel
9mm BCG
9mm hammer
9mm buffer

[tujungatoes]

I bought an olympic 9mm upper. No modifications or caliber specific parts. Just slap it on and shoot.

[automatikdonn]

$200 for an adapter... A whole new lower can be done for 150 and you get a complete rifle.

[EscalonShooter]

Get a Spikes magwell adapter, a 9mm buffer, a cmmg 9mm lower from Primary Arms http://www.primaryarms.com/product.s...&categoryId=94 .. all you need are a couple of mags and you are good to go......My 9mm AR gives me silver dollar size groups at 100 yds on iron sights...at 50 yds nothing is off limits......1500 rounds down the tube and really reliable.....what ever you do, make sure you get a 9mm ramped bolt with the upper(the cmmg upper comes with it), that way you do not have to change hammers.....