With some free time over the holidays, I decided to do another TandemKross Spitfire and Manticore X build. Inspiration for this project came from a couple of sources. First, I saw that TandemKross had released a Buffer Tube Mount for the Manticore X. This would allow some new options other than what the standard Picatinny mount provided. Second, my original Manticore X build, along with the Spitfire review build, were both black. It was time to add a little color. So this time around, I’m using a red Spitfire barrel and a few other red bits. Keeping in mind that the Spitfire and Manticore X are ideal for Steel Challenge, I went with a light and fast theme.
Digging through my boxes of odds and ends, I found a spare carbon fiber stock tube in red. Further digging produced a very minimalist AR stock. And from there, my plan came together. With a little drilling, some tapping and threading, plus some 3D printing, and I had the exact rifle I pictured in my head. Rather than a review of parts I’ve already covered, I want to share how this project went from a simple idea to the complete rifle pictured.
Planning this TandemKross Spitfire and Manticore X Build
Watching videos of rimfire competitions, I see a lot of colorful firearms. Red is probably one of the most popular colors, and we all know red makes you faster, right? Well, I knew I had the spare red carbon fiber tube, and I wanted a red barrel to match. Thinking about options for the actual buttstock, I considered having something 3D printed. On paper (and by that, I mean in my head) it sounded cool, but I also figured that even with an 11.5-ounce barrel, that would be unbalanced. So a little weight at the very back wasn’t a bad idea.
Since the carbon tube included an adapter to match the diameter of an AR buffer tube, I was mostly set on the front end. Mating the Battle Arms Development stock (it’s an older version of this) would require a printed part to match the diameter as well. While I was picturing a simple split ring to get the job done, you’ll see in the photos below that my friend went above and beyond. The final hurdle was adding the tiniest set screw to the TandemKross adapter, to keep the tube from rotating. With all these issues sorted out, I was ready to round up all the parts.
Details of the custom bits
The carbon fiber tubing is a leftover piece that Karl from Crazy Ivan had sent me years ago. Pairing it with the adapter he offered for his chassis simplified the process. I just had to have the TandemKross Buffer Tube Mount tapped and threaded, which was a challenge. It’s very thin, so there aren’t a lot of threads. And I had to file down the set screw. Luckily, it only needs to add a small amount of friction. If you are doing this yourself, get the smallest set screw (or grub screw) you can find, and be prepared to file it down some. Tighten it as little as possible, with some blue thread lock for extra security.
As you can see from the photo below, my friend went all out with his printer and skills. His adapter not only fits the buttstock perfectly, it even goes inside the tube to prevent it from being crushed. I’m certain that’s a bit overkill, but at the same time, it looks great and any extra weight isn’t a concern. Speaking from an aesthetic viewpoint, the matte black buttstock and red tubing are a perfect match for the Spitfire and Manticore X as well. I love it when a plan comes together.
The rest of this TandemKross Spitfire and Manticore X build
Since I already reviewed the Spitfire and Manticore X separately, I won’t go into too much detail for either one. You can click the links at the top of this article to read those reviews. For this project, I had three receivers to choose from. My Fletcher 11/22 has a rail that interfered with the Eagle Eye Fiber Optic M-LOK sights. Although my Elite 22 receiver had a shorter rail, it’s integrated, and it seemed like a waste to use that receiver with open sights. That left a plain old Ruger OEM 10/22 receiver, which is probably what most people will use as well.
Hiding under the barrel is a red TandemKross V-Block for a little extra color. Although I should have used their KrossFire bolt, I had a spare from Tactical Innovations. It’s actuated by the TandemKross Spartan Skeletonized Charging Handle, also in red. I really like this oversized handle with some material cut out to keep the weight down for reliability. Continuing the red theme is a buffer from High Tower Armory. A TandemKross Companion Extended Magazine Bumper makes reloads easier. And the Spitfire’s thread protector was swapped out for a Game Changer Compensator.
Wait, there’s more!
There’s one thing I didn’t mention, and that’s the total weight. With an empty magazine, the entire setup weighs just 3 pounds, 6.1 ounces. Yes, I’ve built a rifle that was almost a full pound lighter than this. But it was terribly unbalanced, and a bit awkward as the stock was straight, rather than angled. This combination of a custom stock fitted to the Spitfire and Manticore X build is nicely balanced. And the sights line up perfectly thanks to the stock adapter which can be set either way. Length of pull is ideal as well, since the carbon tubing was cut to fit. In other words, this build is about as perfect as I could ask for.
As always, I’d like to give credit to those who had a hand in this project. While Karl from Crazy Ivan is no longer with us, his legacy will continue under new ownership (Creekside Custom). Matt from Summit Precision helped out with the 3D printing. And TandemKross always offers support whenever I get an idea worth building.