The quality and affordability of the CZ Scorpion line of pistols and rifles led to their immediate popularity. As a result, a robust aftermarket of parts quickly appeared from companies such as Manticore Arms, HB Industries and Magpul.
Unlike other pistols and rifles based on a submachine gun design, Scorpion factory magazines are very affordable, averaging about $20 each. Made of polymer, they are available in 10-, 20- and 30-rd. capacities. Nevertheless, there are aftermarket box magazines available from several manufacturers in 20-, 30-, 32- and 35-rd. capacities, as well as 50-rd. drum magazines.
Extended controls—charging handles, safety selectors and magazine release—are popular accessories for the Scorpion, as well as aftermarket handguards and are produced by Manticore Arms and HB Industries.
Arm braces for the Scorpion pistols are available from SB Tactical, including the side-folding EVO as offered from the factory and sliding PDW brace, as formerly offered on the Scorpion Micro. Gearhead Works also makes a Scorpion version of its Tailhook-type brace.
A common complaint for Scorpion owners is trigger pull (our test samples averaged between 8 and 10 lbs.), and HB Industries makes reduced-weight trigger spring kits.
While less widespread, accessories are also available for both the original Bren 805 and the newer Bren 2 Ms version, including extended controls and handguards from HB Industries and Manticore.
Those with the 5.56 mm version of the Bren rifle or pistol you can use any AR-15-type magazine. At this time, owners of 7.62x39 mm Brens are limited to the factory 30-round magazines, which have an MSRP of $30 each.
Although SB Tactical only makes a brace for the original 805 pistol version of the Bren, the Bren 2 pistol uses an endcap that is threaded for an M4-style buffer tube, making it compatible with any AR-15 pistol arm brace system.
CZ Bren 2 Ms Field Notes
- At this time, caliber conversion kits for the Bren rifles and pistols are not available through CZ-USA.
- The pistol grip molded into the lower housing has interchangeable backstraps (currently unavailable through CZ-USA) and a storage compartment.
- The Bren 2 Ms pistol comes supplied with a receiver end cap with provision for an M4-style buffer tube for mounting an arm brace. We mounted SB Tactical's SBA3 adjustable arm brace with the company's Buffer Tube Folding Adapter (BTFA). While the stock on the Bren rifle folds against the right side of the firearm, the height of the M4-style buffer meant that folding it to the right side blocked the ejection port and the rifle's case deflector kept the brace from locking in place. Orienting the BTFA to allow the brace to hinge to the left side of the Bren 2 Ms pistol worked perfectly. The charging handle had to be moved to its right side position, but all of the other left side controls were accessible and the pistol could be fired with the brace folded. The BTFA adds only inches to the overall length of the pistol when the brace is folded.
- The front sight post of the Bren 2 Ms pistol is "dual adjustment." Using the sight tool to press the front sight detent all the way down allows the post to be adjusted for elevation. Pushing the detent part of the way down allows for the top portion of the post to rotate independently, letting the shooter orient the luminescent dot towards the rear sight without changing the elevation adjustment.
- Unlike earlier versions of the Bren, the bolt-and-carrier group on the Bren 2 is user-serviceable. Pushing out the firing pin retaining pin allows the firing pin to be removed. With the firing pin removed, the operating pin (cam) can be removed, which allows the bolt head to be removed from the carrier. At this point, the entire bolt carrier is field-stripped for cleaning purposes.
- For sling mounting options, the Bren 2 Ms is equipped with front metal half-inch sling loops and rear metal 1" sling loops on each side. In addition, there are Magpul-style QD sling sockets on each side at the rear of the receiver.
- The Bren 2 Ms comes supplied with a well-stocked cleaning and maintenance kit. It includes cleaning rods, a patch jag, patches, oil, bore brushes, chamber brushes, cleaning brushes, a combination Torx wrench and gas port pick, a multi-tool that includes a gas tube scraper and a sight adjustment tool.
CZ Scorpion EVO 3 S1 Pistol and Carbine Field Notes
- One of the best aftermarket accessories for the Scorpion pistol or rifle is an extended charging handle. The factory handle is small and hard to grasp without running your hand against the Picatinny rail on the top of the receiver. One of the best aftermarket charging handles is the Fixed Charging Handle made by Manticore Arms. The Scorpion design allows for a charging handle to be used on both sides of the firearm at the same time and Manticore recommends using its charging handle on the primary side and placing the OEM charging handle on the operator's secondary side of the firearm.
- The factory Scorpion folding and telescoping stock is designed for the factory low-mounted receiver aperture sights. The factory stock's drop allows for it to be folded without covering the ejection port, allowing the rifle to be fired with the stock folded. The Magpul Zhukov-S stock has a straight profile, requiring the use of AR-height sights. When in the folded position, it covers the Scorpion's ejection port, preventing the rifle from ejecting properly and causing jams if the rifle is fired with the Magpul stock folded.
- Scorpion pistols (with the exception of the Micro model) and rifles have metal HK-style sling loops at the front of the receiver and molded-in sling loops at the rear of the receiver on both sides. The Micro pistol only has the rear receiver loops.
CZ Scorpion Bullpup Chassis Field Notes
- While Manticore Arms/CZ-USA designed the bullpup chassis to be compatible with many aftermarket parts, including grips, charging handles, magazines and Manticore and HB Industries handguards, we discovered when assembling our Magpul Edition Scorpion into the bullpup chassis that the Magpul MOE-EVO grip was not compatible with the chassis grip mount.
- Scorpion pistols can also be used with the chassis, but they must be registered as short-barreled rifles according to the NFA, due to their barrel length, as placing them in the bullpup chassis turns them into a rifle.
- The bullpup chassis requires the use of a cheekpiece to cover the rear portion of the top receiver Picatinny rail on the Scorpion, which becomes the rifle's "buttstock." This raises the rifle's line-of-sign above the typical AR-15 flat-top height. When testing the bullpup with a scope in an AR flattop riser mount (1.59" to scope center height) we had to also use a section of Picatinny rail extension that added an extra 0.5" of height to achieve the correct scope height. The optic riser supplied with the bullpup kit gives approximately 1" in height and is perfect for a red dot or reflexive sight on a "low" mount. We used a Sig Romeo 5 with its factory low mount.
- While in the chassis the factory Scorpion's front and rear sling loops, on right and left side, are still accessible. In addition there is a 1.25" sling slot molded into the rear portion of the stock, as well as Magpul-style QD sling sockets on each side.
- We found a vertical foregrip, mounted to the M-LOK slots of the Scorpion's front handguard, to be helpful for holding and controlling the rifle when in the bullpup chassis.