I am in process of building a 9mm on Rock River lower using a Rock River upper, the latter of which I am still waiting delivery. Be that as it may, I couldn’t decide which mag block to go with; the Hahn dedicated, which inserts from the top, or the non-dedicated VM-Hytech mag block so I ordered both from Brownell’s. I also ordered one of Brownell’s 25 round 9mm mags since it should fit either mag block i.e., it appears to be an UZI spec mag with the mag retention cut for both UZI (for the VM-Hytech block) and Colt (for the Hahn block).
Now for my question: The Brownell’s 25 round magazine fits both blocks as I thought it would but it fits very loosely in the Hahn block, rocking fore and aft and side to side when wiggled (so to speak) and the fore/aft movement is, to me, significant yet it fits very tight in the VM-Hytech block, almost difficult to insert (takes a good slap to seat and does not move at all in the block). Does anyone know if this is typical of the Hahn block (a very loose fit of the 9mm mag in the block) and will it cause any feeding or function problems?
Both blocks are nicely made, beautifully machined and excellent fit in my RRA lower but I am surprised by the loose fit of the Brownell’s mag in the Hahn block and tight fit in the VM-Hytech block. Needless to say I have no idea how either will function since I don’t have my upper yet.
Any comments regarding your experience with 9mm mags in either mag block would be greatly appreciated.
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I have no experience with the Hahn, but when I returned home, my 9mil carbine with the VM block was waiting for me. I also have the RRA upper (which I waited 13 months for.)
The whole setup has been running great so far. I have 200 rounds through it - 100 FMJ and 100 lead rounds with zero malfunctions or parts breaking. I like the tight fit of the VM magwell block. The only downside is getting used to mag releases with the Uzi mags. Being used to the M4, I’ve already hit the wrong mag release a couple times. That being said, I would probably stick with the VM given the choice.
Thank you for the feedback. You haven’t experienced any problem with 9mm mags not fitting the VM mag block? When I received the VM block from Brownell’s I had also ordered one Brownell’s mag. It is a tight fit in the block but it does go in with a healthy tap. Today I received two IMI UZI mags and and neither will insert into the VM mag block at all, well maybe a hammer might get them in (too tight of a fit). I also received two Metalform mags I ordered for my Hahn block and they fit beautifully without excessive looseness like the Brownell’s mag. I’m at a loss as to what to do about the VM mag block that won’t accept genuine IMI mags, other than to contact VM and see what’s up.
Hahn, Hands down. If you go with a VM you have to retrain yourself not to hit the mag release. I have had a few differant blocks over the years and the Hahn is my favorite by far.
If you may have to use that weapon under stress its better have a weapon that operates “normally”. If your used to shooting ARs the trigger finger drops the mag, its just 2nd nature, unless you have a VM block. In the case of the a VM the hand that should be grabing your next mags has to 1st drop the almost empty or completly empty mag first, i.e. slower reloads.
Hahns just flat out work, you dont have to have someone mill your uzi mags either. While Moded Uzi mags are still cheaper then COLT factory steel mags you have to hope they were done right and that they will work every time, unlike the COLT mags which in my experance have always been “Plug and Play”.
If you decide to go with a VM, hurry up and buy one, most of the larger retailers have stop carrying them. Honestly I dont know if they are even in production at this point?
2 plus years later I find you are correct. The Hahn is the way to go. The VM was sold because it was a PITA and the mag release thing was goofy. The Hahn now has several thousand rounds through it with the RAA 5.56 lower and RAA 9mm upper and I have yet to experience a single malfunction. One can’t ask for better service from a firearm put together with one’s own hands from parts and pieces than that.