Stealth Arms Platypus Unboxing and Optic Installation
Welcome back to Jim's Armory. In this one, Jim unboxes the Stealth Arms Platypus, a 9mm 2011 with an unusual claim to fame: it runs Glock magazines instead of the double-stack mags you'd expect on a 2011. He walks through what comes in the box, digs into the build sheet, and then mounts a Holosun 507Comp Ronin Edition using a mounting method that's a little different from what he's used to. Here's how it all went.
Is It a Duck or a Beaver? Unboxing the Platypus Jim's Platypus arrived in a leather bag, which he notes is normally an upgrade but is currently being thrown in for free with the gun. Stealth Arms builds these to order with an advertised lead time of 12 to 14 weeks, though Jim found this one already built out in the wild rather than waiting on a custom order. The gun is available in two magazine flavors: Glock-compatible or P320-compatible. Jim already owns a SIG P211 (also a 1911-pattern gun that runs P320 mags), but he wanted to try the Glock-mag version specifically to see how it handled - Glock mags typically reflect a steeper grip angle, but the Platypus keeps the classic 1911 grip angle despite feeding from them. The gun ships with a pair of 17-round magazines.
Pulling the gun out, Jim is immediately taken with the grip texture, an aggressive, cactus-like stippling that's mirrored on the slide's front and rear serrations. Notably, the frame and grip are a single piece rather than a separate grip module with removable panels - a real departure from the 2011s Jim usually covers. He's already planning a full teardown to see how Stealth Arms pulled that off, including how a small panel toward the rear appears to allow the trigger to slide out.
What's in the Box Beyond the gun and two magazines, the box includes a spare fiber optic front sight, a spare rear sight, an extra mainspring housing pin (useful if you want to remove the magwell, though Jim isn't keen on that texture rubbing against him during carry), a handful of Allen wrenches, and two sets of shouldered optic screws - one set for the Holosun 507C and another for the RMR/SRO/RCR/RMR HD footprint.
The Build Sheet The included build sheet lists the specs for this particular gun: a black nitride finish on the slide with smaller parts like the hammer pin, hammer strut, mag catch lock, and mainspring housing left blued, and a trigger pull weight of 3 to 3.5 lbs. Jim notes that buyers configuring their own gun can choose a lighter trigger option, and he may look into converting this one down the road.
Removing the Optic Plate Before mounting the optic, Jim needs to get the factory sight plate off - and it's not the usual drill. There are no screws visible on top, so the slide has to come off first. From there, he pulls the firing pin stop using a punch, then finds a small set screw underneath (5/64 Allen) holding the plate down. The plate itself has a tab on the front that indexes into a groove on the slide, so it needs to be lifted and wiggled slightly to clear.
While in there, Jim discovers the firing pin was installed backward from the factory - when he pulled the firing pin stop, the pin and spring came out separately. He notes it isn't a confidence-inspiring find, but it's an easy fix: flip the pin around, give it a twist, and it seats back in properly.
Pro-Tip: If a screw hole on an optic plate doesn't show daylight underneath, don't assume it's a blind hole - some sight/optic screws run down into the extractor tunnel, so use the manufacturer-supplied screws when they're included, since they're already sized for that gun.
About the Optic Cut Jim initially thought the built-in RMR-pattern cut limited buyers to a fixed footprint, but corrects himself on camera: Stealth Arms actually offers several optic cut options (RMR pattern, DeltaPoint Pro, and others) that you select when ordering the gun. He got lucky that this particular sample happened to already support the footprint he wanted to run. The upside of the direct-mount pattern is a notably low optic footprint.
Installing the Optic: Vibra-Tite Instead of Loctite Jim has moved away from using Loctite on optic screws, instead reaching for Vibra-Tite VC-3, an elastic-style compound rather than a traditional threadlocker. It goes on the screw and is allowed to dry before the screw is installed - about 10 to 15 minutes - so it hardens in place rather than curing inside the threads, which would reduce its resistance. He also likes that, unlike Loctite, screws treated with Vibra-Tite can be removed and reused.
With the compound cured, Jim torques the Holosun 507Comp's screws to 15 inch-pounds using the factory-supplied hardware. For the rear iron sight, Stealth Arms doesn't provide a torque spec, only instructing users to snug it down - so Jim applies Vibra-Tite here too and snugs it to roughly 10 inch-pounds after seating its two indexing lugs into the slide.
What's Next for the Platypus With the optic mounted and the gun wiped down, Jim is clearly enthusiastic about how the finished piece looks. He plans to take the Platypus out to the range for a full review in the near future, and a teardown is on the list as well, given how curious he is about the one-piece frame/grip construction and how the trigger assembly comes apart.
Final Thoughts The Stealth Arms Platypus stands out for its Glock-magazine compatibility, integrated grip module, and direct-mount optic cut, and Jim's first impressions - aside from the backward firing pin - are largely positive. The real test will come at the range. Stay tuned for that review, and subscribe so you don't miss it.
