We Like Shooting interviewed Sven Jonsson of Manticore Arms last weekend. Sven explains how the Bullpup Scorpion was developed and how simple the conversion will be.

Sven came up with the idea a two years ago and it has gone through some significant changes. Most importantly the chassis has the approval of CZ-USA and it seems, from the interview, that they collaborated over its evolution. I posted about the bullpup scorpion and noted how much the polymer chassis appeared to look like the same polymer as a factory Scorpion Evo3. That is because it is the same polymer and CZ is manufacturing the chassis.

Part of CZ-USA’s input was to maintain as much original components as possible. This is actually a very smart move as it allows endless modification for the end user with any after market parts. This also simplifies manufacturing as they only have to make the chassis. According to Sven there are about eight unique parts to the bullpup kit. Not including off the shelf parts like springs and detents.

According to the interview, the chassis recycles almost everything from the Scorpion lower receiver. The trigger and trigger pack is reused while the pistol grip is re-positioned forward. I am sure many of you are concerned about the trigger feel as bullpups typically have awful triggers. Sven mentions his design for the transfer bar is patent pending and due to the design, the trigger bar only adds about 3/4 lbs to the trigger pull weight. More importantly the transfer bar will directly reflect what the sear does to the re-positioned trigger. You will feel the trigger reset and a direct feel for the break when the sear is tripped.

The chassis has three points of contact with the Scorpion upper receiver. The rear is pinned through the block where the pistol grip used to be, the same front take down pin position and there is a hook at the front of the chassis that hooks onto the factory CZ Scorpion carbine handguard. The position of this hook is specific to the exact position relative to the handguard. So if you change handguards, you may need to modify the hook. Sven considered this and so he made the hook a replaceable component. Not only does this take future modification into consideration, it is also considers longevity of the chassis. If the hook was molded as part of the chassis, you lose an important point of contact if the hook is somehow damaged.

As I suspected, the protrusion above the pistol grip is a cross bolt safety. It engages a slot cut into the transfer bar. This way the entire trigger system is locked out.

Below are photos Sven sent us to highlight the Bullpup Scorpion chassis.

Top is stripped receiver. Bottom completed receiver.

Complete top down shot of lower receiver with all parts installed.

Receiver with no parts installed.

Trigger pack installed in the bullpup lower receiver. You can also see the ejector installed and the bolt hold open lever.

Looking forward of the magwell towards the front of the lower receiver. You can see the Trigger Bar, and how it is retained by two “Trigger Bar Hats” and also the front hook the engages the M-LOK slots on the underside of the forend. The hook is replaceable so it is in theory possible to mate with forends beyond just the OEM and Manticore Arms forends if custom hooks are made.

The pocket in the lower receiver that the trigger pack drops into. It is held in place by a screw from the underside, just like on the OEM lower receiver. You can see the black oxide coated trigger bar in the pocket right below the word “PROJECT” that is molded into the lower receiver- what that says is a little Easter egg hidden in the lower receiver. 😉

Closeup of trigger pack with Trigger Shoe installed (note the two legs of the trigger shoe and the integral cross pin that engages the slot on the Trigger Bar) part is in the white, production parts are black oxide finish

Interestingly the transfer bar is a push rather than a pull. If the trigger pulled the bar forward, it would actually require more material and make the lower receiver taller than necessary. This design allows for the height of the lower receiver to be as short as possible.

The Bullpup Scorpion will be sold as a kit via CZ-USA and Manticore Arms. There has been interest by some FFLs to buy kits and build complete bullpup rifles using donor Scorpions. The kit will sell for $400. And from looking at the photos Sven sent us, it seems like the conversion is pretty straight forward. The kits are in production now and they are expecting an end of the year release for these bullpup scorpion kits. Hopefully we will get one in to review.