Fall Build Fest Continues - 15% OFF GUN PARTS THIS WEEK
Use Code: PARTS15

Fall Build Fest Continues - 15% OFF GUN PARTS THIS WEEK
Use Code: PARTS15

AR-15/M16 9MM DROP-IN CONVERSION BLOCKS

AR-15/M16 9MM DROP-IN CONVERSION BLOCKS Reviews & Ratings

One-piece, machined aluminum block converts AR-15 lower receiver to 9mm. Compatible with all, Colt-type, 9mm upper receivers, the feed ramp is cut for reliable feeding with all types of ammo, including hollow point and frangible ball. Roller retention device holds block securely in receiver, prevents accidental release. Hardened steel ejector, feed ramp and bolt hold open give long service life; last-round-hold-open feature on bottom-loading model works when used with Colt magazines. Also works with modified UZI magazines but last-round-hold-open will not function. No receiver modification required. Top-Loading Block installs from the top of the lower receiver and Bottom-Loading Block installs from the bottom of the lower receiver. SPECS: Aluminum, black, matte finish.

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Reviews Summary
Overall, customers rave about the AR-15/M16 9MM Conversion Blocks, highlighting their excellent fit, build quality, and reliable performance. While some users faced initial fitting challenges, many found it easy to install, and compatibility with various magazines was frequently praised. However, a few noted potential issues with specific lowers requiring additional adjustments.
What Reviewers Are Saying
Product Quality
85%
Many reviewers express satisfaction with the build quality and materials of the conversion blocks, praising their snug fit and high standards of manufacturing. This theme resonates strongly among users who have tested the product extensively, confirming its reliability in various configurations.
Ease of Installation
75%
Reviewers commonly describe the installation process as straightforward, with many appreciating its drop-in capability. However, some encountered fitting issues with specific lowers, suggesting that users should be prepared for minor adjustments in certain cases.
Compatibility with Magazines
60%
The conversion blocks are highlighted for their compatibility with a variety of magazine brands, especially Metalform and Colt. However, some users reported needing to modify magazine catches for optimal performance, indicating a slight learning curve depending on the user's setup.
Reliability and Performance
70%
Users commend the conversion blocks for delivering flawless operation across numerous rounds, even with various types of ammunition. The consensus is that once properly installed, the product performs as intended without malfunctioning.
Adjustments Required
50%
A few reviewers encountered issues that required fitting and adjustments before achieving a perfect setup. This theme highlights the variability in lower receiver specifications and user skills, suggesting that some will need to be comfortable with minor modifications.
Customer Photos & Videos
5
Hahn makes the best conversion adapter
Hands down the best, tight tolerances, snug fit. Tried them all, none of them came close to the consistency of this adapter. I wouldn't skimp on this, i recommend it over the colt branded 9mm adapter. My weapon has not had one malfunction since i installed this. 500rds so far, Subs, FMJs, Hollows, to flat noses. No bending the ejector or making new ones. Flawless, just use brownells or Colt/metalform mags and you will thank me later. ASC Magazines will work but shave the rd follower down to a rounded edge. Have had no issues since.
Would you recommend this? Yes, I would recommend to a friend
5
Top quality
I was impressed with build quality.
5
Top-Loading 9mm Conversion Block by HAHN
Quality product, easy to install. I havent had a chance to try it yet but fit and finish looks good. As always Brownells customer service was excellent in getting this item to me in a timely manner, thanks Brownells!
5
Works Very Well
Works well with C product metal form mags. Drop in is easy to take in & out if your swapping uppers. I did have an issue with the mag catch not poking out enough to grab the magazine. I went with a 9mm Mag catch and then had to take material off the base by the post. This caused it to can't into the wag well more with success. No fault of the drop in.
5
Great product
I bought this to use in my SBR lower with a10.5" upper. Functions perfectly with metalform mags with 3 different bullet weights. Easy in and out in about 3 min. At the same time I bought a designated 9mm lower for a 7.5" pistol. Nothing but malfunctions using the same mags.
5
Fits and works great!
As the headline says, this block fits and works great and the finish is fine. The Metalform 32 round magazines slide in and out and lock in place smoothly. The rounds feed and eject perfectly and the bolt locks open when the magazine is empty. What more could you ask for?
5
Great 9mm block
Function has been 100% with 1000+ rnds of misc ball and long ogive HP ammo in following setup, Spikes lower, Spikes 9mm buffer, RRA Upper with CMMG ramped 9mm bolt and CMMG barrel, Metalform, Colt and Spikes mags. Installation is easy as long as you are comfortable performing basic assembly on an AR lower as the bolt catch must be removed and reinstalled. Works just as well as my dedicated Colt. Mileage may vary depending on the quality of your lower.
5
THE BEST! & BETTER THAN ORIGINAL COLT!
I have fired an original select fire full-auto COLT SMG (M16/9mm) and have had many malfunctions using 147 grain 9mm ammo. I bought a Rock River Arms 9mm upper receiver assembly and this HAHN Top-Loading 9mm Conversion Block. I also am using original COLT M16/AR15 32 round magazines. I have not experienced any malfunctions with my converted AR15 using 115 grain & 147 grain 9mm ammo in semi-auto or full-auto modes of fire. I also recommend the ENIDINE Hydraulic buffer for recoil reduction and slower rate of fire in full-auto mode. Call me if you have any questions.Cell [@]. GUN SLINGER VIDEOS