I was setting up guns at the range last weekend when Jacob, my aide with all things tactical, brought over the strangest looking rig I’d ever seen. It looked a lot like a space-age take on the old Sterling submachine gun. The exterior was all anodized aluminum and picatinny rail, and buried beneath the bulk was the operating mechanism, a Glock 19.
The Glock I understood. The rest was new to me. I’d seen these before, but never in person. The Hera Arms Tiarii is a very complex device with a very simple purpose. The external frame adds usable tactical space to what is an otherwise limited platform. In other words, it gives your pistol the useable surface area and advantages of a carbine. And it does it instantly.
The Tiarii slides open to accept a pistol. There are specific versions made for a variety of service pistols. The objective is allow one gun to serve multiple roles. A sidearm that is very useful in close quarters can be inserted in the Tiarii during a longer stand-off situation, allowing the operator the advantage of optics, a stock, lights, forend grips, etc.
Simply insert the gun in the frame, slide the front and back halves together (an action that is guided by aluminum rails), and tighten down a knurled nob. Your pistol is now a carbine.
With rails on the top, bottom and sides, there’s ample room for absolutely anything you might want to add on. On the right side of the pistol, milled clearance ensure that the Tiarii won’t disrupt ejection. A charging handle on the left side of the Tiarii operates a lever inside that catches the frame, not the barrel, of the pistol. The charging handle is incredibly easy to use and the mechanical advantage is actually an improvement over traditional pistol/slide operations.
The logical benefits
Besides the obvious advantage of extra rail, the Tiarii offers some useful ergonomics. The extra length on the fore-end allows you more grip. The extra stability afforded by the Tiarii, in combination with the added mass, really stabilizes the pistol. Repeat shots are easier than they are with a naked Glock.
Also, an angled fore grip, like the Magpul Angled Fore Grip, is helpful for stabilizing the fore-end and perfectly legal. A vertical fore grip is not legal, according to the ATF. The language here is very important and it seems to be open to some interpretation (much like the way SIG’s new arm braces on AR pistols managed to gain ATF approval). The angled fore grip is angled. My interpretation is that he ATF’s original language wasn’t broad enough to also restrict angles. Some have actually asked the ATF, and this letter is an example of the ATF’s response, though it doesn’t explain why it is legal, exactly. If you want to be safe, write and ask.
A stock on the back end stabilizes the gun even more, but that does require some paperwork from the ATF. Add a stock and this becomes an short barreled rifle. Don’t do it unless you get the clearance and stamps.
One thing the ATF isn’t concerned with is the increase in the distance between the sights. A good pair of back-up sights is a must, though most will simply want to run the Tiarii with a red dot on top, which is even faster.