The Unimag from Ross & Zheng Engineering was created with the intent of having one magazine that was capable of working with the majority of popular cartridges that are chambered in an AR15, STANAG magazine configuration (or with similar dimensions). This means that the Unimag is designed and tested with the following cartridges in mind-5.56x45mm, .300BLK, .204 Ruger, 5.45X39mm, 6.8mm SPC, 7.62×39, 6.5mm Grendel, and .458 SOCOM. Too new at this point, but testing will probably be eventually done, but to add to that list is the .224 Valkyrie.
Now, the majority of those cartridges generally work well in STANAG magazines, in fact one of the premises of their designs was to specifically work in STANAG magazines. Now, sometimes there will be reliability issues with a standard issue STANAG design, which is why we have 6.8mm SPC specific magazines available today. But what really intrigues me is the ability for the Unimag to work well with the Soviet 5.45x39mm and 7.62x39mm cartridges. Previously these cartridges did require their own STANAG dimensioned magazine in order to fit enough cartridges in them and work reliably. One particular issue with this is in the case of the 7.62x39mm 30 round STANAG magazine, it has this very distinct curve due to the taper of the round. One issue with this fact is that you can’t use these 7.62x39mm magazines in a standard STANAG magazine pouch, or even fit the same profile. But with the Unimag you can, which is why it excites me to know this exists.
The steel magazines works by having a tilting follower, that is anti-tilt in the front (standard on many STANAG magazines), but has a spring loaded lever that allows the follower to actually accommodate to the taper of the different cartridges. At the same time, the upper portion of the magazine walls are designed to actually flex with the different size cartridges that are being used.
But the Unimag has actually existed for a while, since at least 2015 when we first reported on it at SHOT Show. The company has also gone through a very strenuous ITAR process with the State Department due to the designer being from China. Hopefully this year they can really start pushing the magazine out there because I for one am very interested in doing some durability tests on the magazine to see if it stands up to the claims of Ross & Zheng Engineering.