Nexus Firearms has evolved the CZ Scorpion into a bearing-delayed, all-billet platform with higher durability, safety and accuracy and a 40% recoil reduction. Nexus offers a fully in-house-manufactured Evo 2 pistol line and complete DIY upgrade parts.
The CZ Scorpion EVO 3/3+ is the hottest-selling PCC ecosystem in America. Demand for magazines alone became so strong that Magpul stepped in with 35-round PMAGs, and then the accessory pipeline opened fully with every imaginable “make it yours” upgrade. The platform became a customization canvas like the AR platform. In many cases, that aftermarket didn’t just support sales — it created more sales, because owners bought additional Scorpions for new builds. With all the positives, there were some design challenges left unaddressed on this price-competitive platform.
Where High Round Counts Expose Design Compromises
The Scorpion is fundamentally a direct blowback system. Direct blowback can be extremely reliable, but it also carries known tradeoffs — especially when you start chasing “faster,” “flatter,” and “softer” in a platform that’s being pushed outside its original design assumptions. Once millions of rounds collectively get fed through a platform — especially one heavily modified with fast aftermarket triggers — compromises that were invisible in factory configuration or before round counts add up.
According to Cody Funk, founder of Nexus Firearms, “Scorpion owners, like us, who were running modified platforms had several recurring issues. We understand that CZ had to make some compromises to keep the cost low; however, some of those compromises like a polymer upper receiver and soft steel bolt have had some downstream impacts, such as bolt deformation that increases the chance of out-of-battery detonations. Some trigger systems were outrunning the bolt speed, which did lead to some out-of-battery detonations. The other concern is when these out-of-battery detonations do accrue, the polymer receiver is not able to safety contain the detonations. “
Funk went on to note, “The Scorpion platform is an amazing cost-effective PCC. With that noted, there are enough customers having these issues that Nexus Firearms has quickly become one of the largest CZ Scorpion aftermarket manufacturers. A lot of these problems start with the relatively soft 42 Rockwell hardness OEM bolt steel. That softer material can wear and deform around the striker block area over time. When deformation keeps the striker block pressed in, the risk window increases for out-of-battery or unexpected detonations. With just our tool steel bolt and receiver, existing Scorpion customers can address these issues without changing platforms.”
Nexus EVO 2 and a Bearing-Delayed Receiver Swap
The PCC market has evolved, and shooters are comparing recoil impulse across platforms. They expect better suppression behavior and have more options than ever. Softer-shooting roller and gas delayed competitors like the Springfield Kuna, Sig MPX, and reintroduced Century Arms AP5 and even hydraulic-buffered AR9 platforms offer far softer recoil compared to a traditional blowback Scorpion.
Nexus’ design approach was to keep Scorpion compatibility with the option to swap out the components. The result is the Nexus bearing-delayed EVO 2 receiver, which is positioned as a drop-in receiver swap for factory CZ Scorpion EVO 3/3+ builds. The upgrade centers around a 6061 billet upper receiver and a simple bearing-delayed operating design. The design delivers increasing safety by ensuring the bolt is fully in battery before detonation. It has a more robust receiver and delays, smooths and reduces the recoil by 40%.
In our side-by-side testing against the Springfield Kuna, the Nexus Evo 2 delivered a similar “buttery smooth” recoil that people associate with roller-delayed guns. We also experienced about a 50% accuracy improvement — attributed to the barrel interface benefiting from a stiffer billet structure versus a polymer upper. The Scorpion platform’s snappy recoil has always been even spicier when suppressed, but the Nexus Evo 2 changes that with amazingly soft suppressed recoil thanks to the bearing delay.
The Bolt Solution - Tool Steel, Hardness and Durability
Nexus tackled the bolt concerns with an Enhanced Bolt built from D2 tool steel with chamfered and radiused edges to reduce wear on both hammer and bolt during cycling. The bolt is heat treated to 58 HRC then finished with nickel boron for increased hardness to 70 HRC. The NiBo finish increases lubricity and makes for easier cleaning and improved wear characteristics. An enhanced guide rod and spring assembly was also designed, including a rebound spring intended to soften the bolt’s rearward impact for smoother operation. Testing the new enhanced bolt upgrade reduced the recoil further by about 5 to 10% over just the receiver upgrade.
Nexus EVO 2 Complete Pistols
Nexus offers DIY parts and complete pistols. In the current Nexus EVO Gen 2 pistols release, they offer a fully Scorpion (3/3+) compatible platform that no longer relies on CZ parts. All Nexus firearms are built from in-house components and select partner components; partners include Timney triggers, Magpul mags/controls, HB Industries handguard options, and optional integrally suppressed barrel setups from partners like Novox Research.
“After we started producing the bearing delayed uppers and bolt assemblies, we had customers wanting complete pistols. In fall of 2025 we now offer a billet matching lower receiver as well, plus all our own and partners’ components as pistol build options when ordering. Customers don’t need to DIY together a Nexus pistol… we offer complete Nexus factory pistols for customers and dealers that are ready to shoot right out of the box,” Cody Funk noted.
The DIY Upgrade Experience: Fast, Simple and Transformational
For this article, I chose the DIY upgrade approach by upgrading the factory 3+ receiver, bolt assembly, trigger and lower receiver for Nexus upgraded parts and saw benefits to each upgrade. The install is straightforward: unpin the upper and remove the barrel retainer nut (using an HB Industries barrel nut tool). Reinstall the factory barrel into the Nexus upper and tighten with the new mounting/bracing system, reinstall the handguard, and reassemble with the new bolt and guide rod system. The Timney trigger was attached to the Nexus lower and the selector moved over from the original housing. All parts simply pivot and pinned together as normal — about a 20-minute install.
The billet upper adds ounces, but trading a few ounces for a major increase in receiver strength and the bearing-delayed recoil reduction is a fair trade. For a PCC shot at 15 yards or less, I really did not expect a dramatic accuracy increase; however, our groups shrank by 50% across all ammo, which would be enough to push most buyers to opt for the $350 receiver upgrade. Notably, the Nexus platform feels delightfully like a completely different gun with only ergonomics remaining similar.
The billet trigger guard allows Nexus to deliver a complete in-house firearm, without depending on CZ parts. For their complete Nexus firearms, it delivers an all metal Scorpion platform with a premier tier of fit and finish that competes in quality with the big names like B&T, Sig, and others. The Nexus trigger housing also does simplify some of the quirky controls into a more AR-ish format which will appeal to a lot of shooters. With the Timney trigger and roller-delayed receiver, the platform is begging the shooter to go fast, and with the improvements, the rounds stack easily on target.
Bottom Line
“There are so many passionate CZ Scorpion customers out there with so much invested into their builds that it would be challenging to even sell them,” Funk noted. “For them, we have a path with our receiver and bolt upgrade that delivers a huge array of benefits and safety to keep them running and enjoying the platform. For customers that want the ultimate Scorpion platform, we offer complete pistols that deliver everything a shooter would want out-of-the-box, including Novox X-SD integrally suppressed barrels, Timney or Rarebreed FRT trigger options, and even Scorpion or 1913 rear stock/brace mount options. All of our builds include HB Industries billet handguards and Magpul accessories. For the dealer or customer, this is the ultimate Scorpion platform.”
As an editor and Scorpion shooter, I enjoyed this fun review that could only be described as transformational. The original Scorpion 3+ felt like a light price-competitive platform, and after the upgrades, the Nexus platform feels like one of the most premium platforms made. My take is that the complete pistols are the best cost-effective option for dealers and customers who inevitably want all the upgrades. The DIY option is best for dealers who have existing Scorpion owners; offering the Nexus receiver and bolt assembly upgrades would be a smart promotion.
Nexus is not just making Scorpion platform parts and firearms — they now also offer a Springfield Kuna and soon CZ Bren 2 products. Their Springfield Kuna lower delivers what many Kuna fans wanted from the start, which is a CZ Scorpion. magazine-fed Springfield Kuna that accepts an AR-15 spec FCG (fire control group). Similarly, the Nexus CZ Bren 2 lower is designed to accept an A-R-5 spec FCG and FRTs. There is certainly more to come from Nexus Firearms.
