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ProMag AR-15 / M16 9MM Magazine Adapter Block

MSRP Price: $59.75
Our Price: $35.00
You Save: $24.75 (41 %)
We currently have 9 available.
Item Number: MAGPM237
Manufacturer: ProMag
Manufacturer Part No: PM237
ProMag AR-15 / M16 9MM Mag Adapter Block

 PM237 9mm Magazine Adaptor Block easily installs in AR-15 lower-receivers to allow the use of 9mm Colt* SMG in Colt* pattern 9mm upper-receivers. The block is constructed of high strength polymer with steel hardware, roller, ejector, and bolt stop.

Product Reviews

(13 Ratings, 5 Reviews) Average Rating:
Money well spent
Ray D. (Western, NY) 1/3/2016 7:24 PM
After reading a lot of negative reviews I wasn't sure I would have good luck with this mag block but after installing it I am pleasantly surprised and quite happy with my purchase. Yes it is more work to install a mag block from the top of your lower because you have to remove your bolt stop but once you do that the block drops right in and stays where you put it. The block feeds and ejects perfectly and holds the bolt open on the last shot which is something that some blocks and dedicated lowers won't do. The only reason this doesn't get 5 stars is because it is plastic and does cause some friction with the metal mags dropping freely. To me that is no big deal but to others it may be. I will be buying a second block when they are back in stock.
Paul Tannahill (Lebanon, OR) 12/7/2015 1:54 PM
I had read on a few different sites that I would likely need to dremel this block for a good fit, and I had no problem with that. I don't want to have to remove my bolt catch to install and uninstall this block, and was easily able to remove just enough material for a snug fit via a bottom insertion. I got it to sit in the exact location it would have been in as a top-install block, so I thought I was good to go for a test-fire. NOPE. The feed ramp was way too low to feed a single round into my JSE-purchased 9MM upper receiver. No problem, I thought. I would just disassemble the block and raise the feed ramp up about 1/8". NOPE. The upper wings on the feedramp scraped against the bolt, marring it. I realized this block would have never worked for me, even if I hadn't modified it, and now I have a block and an upper kit I can't return for refund. Ugh. I guess I'm left with purchasing a much more expensive block, or maybe even a dedicated 9MM lower receiver to even be able to use this upper.
bolt catch
richard jensen (Corte Madera, CA) 9/22/2015 12:15 PM
bolt catch is a little loose mag falls out when firing any sugestions ADDED BY JSE 09/23/15 I'm guessing you meant mag catch? Any time we have had an issue with the mag not being held sufficiently by the mag catch we have located an alternate mag catch lever with a little longer tab. It doesn't happen often, but when it does that is what we do. I don't know for sure of another way to rectify the issue.
Good buy may need tweeked.
norman huff (Kingsport, TN) 9/11/2015 4:11 PM
Works just fine on my build. Had to Dremel just a bit on the feed ramp but, was worth it to save 100.00
Worked flawlessly after a slight mod.
seth glass (Rockville, MD) 11/29/2014 11:44 PM
I wasn't about to remove the bolt stop from my m16 to install this, so I tried modding the adapter. With a little trim work using a pocket knife it slides in just fine from the bottom of the gun. I put 300 rounds through it today in full auto, it didn't miss a beat.