In a previous video, Brownells Gun Tech Steve Ostrem gave us an overview of the modifications necessary to turn a standard 5.56/.223 AR-15 into a 9mm Luger (9x19mm) “AR-9” pistol caliber carbine. Now, he shows us how to install the Stern Defense Magwell Adapter for Glock® mags. It’s a drop-in part, really easy to install, but what’s so impressive is how secure and solid the completed installation is. The mag is NOT going to shift around under fire and potentially cause a jam or failure to feed. And Stern’s adapter is designed to lock the bolt open when the last round clears the chamber. Brownells part #100-027-483; also available for SIG P320/S&W M&P mags, #100-033-498.
Overview – Converting a 5.56 AR-15 to 9mm:
More Brownells videos:
Note to readers: Please click the share buttons above or below. Forward this article to your email lists. Crosspost on your blog site, social media, internet forums. etc.
I can't get my stern defense 9mm adapter to install correctly. PSA 5.56 lower, foxtrot mike 9mm upper. The corners on the silver feed ramp block are hitting the inside corners of the upper receiver. Sent upper back to FM, they installed new receiver but it's still doing the same thing. Stern defense says it's a problem with FM upper. FM says it's the adapter. I'm out of a lot of money for something that doesn't work.
THIS ONLY WORKS WITH MILSEPC RECEIVERS IT WILL NOT WORK WITH THE CUSTOM SHARPS BROS AND CUSTOM SPIKES TACTICAL LOWERS LIKE THE SPARTAN OR THE JACK LOWERS
Where can I buy this adapter
Just got one of these…it works very well for anyone looking to purchase…I got the one to use Glock mags…Absolutely recommend
What about bcg??
Will this adapter work with any 9mm mags or just Glock mags?
Standard buffer ?
Just buy a 9mm lower!
Bolt isn't closing all the way. Looks like the ramp is too tall. (FM9 BCG from Foxtrot Mike)
Do I need a special trigger? I bought this and I can’t get it to feed correctly, also the bolt doesn’t lock open reliably, if I tap the receiver slightly or bump it, it releases the bolt catch, also my KCI glock mags keep falling out of the bottom after each shot fired… i was
At the range today, and left feeling defeated, I contracted stern and they are going to exchange my defective one for a new one, hoping that fixes the issue.
Do the mags drop free easily?
I bought a Brownells stripped upper receiver and a foxtrot Mike ar15 9mm barrel from Brownells but the upper is too small for the barrel to go all the way through.
Will a 9mm bullut go down a 5.56 barrel?
looks nice except for the big white letters on the side.
So I'm interested in buying a 9mm upper and this stern defense mag adapter. Do I have to switch out my buffer and spring from my .556 setup in order to run 9mm?
Stern, if you're listening, instead of tool operated set screws why not spring or mechanical tension that can be operated one handed. Two buttons on the side, squeeze to insert, release to lock in. This could work for the tension inside as well as along the lip of the mag well. Extending pins inside and hooks along the bottom edge with the tension pulling up. If you make one I'll test it for you.
Now all I need is some magazines… man, California sucks
Well that was easy.