It is hard to believe the KelTec SUB2K format is now 24 years old. The first Gen 1 9mm and .40 S&W SUB2Ks rolled off the line in 2001. KelTec has always delivered extraordinarily unique guns. The SUB2K, as they became known by owners, was the first modern firearm with the ability to completely fold in half. It remains a unique design which continues as one of KelTec’s hottest-selling models. Based on our testing, there is a lot to love about the newest Gen 3 SUB2K in the very capable, light-recoiling 5.7x28 round.
SUB2K Gen 2 & 3 Updates
The latest SUB2K Gen 3 retains a direct blowback operation via a simple tube-mounted ambi charging handle that serves to lock the action open. Updates from Gen 2 carried forward were the much-improved trigger, 1/2x28 muzzle threading, more ergonomic and slim MLOK and optics-compatible handguard, and full-length bottom-mount Picatinny rail. The Gen 2-3 stock is an updated design for more ergonomics that includes a simple three-position stock with sling loop, O-ring mount and integrated QD-mounts. Changing stock positions requires driving out the rear buffer disassembly pin and aligning the stock adjustment holes to one of three positions.
The Gen 3 design jump was the addition of an aluminum trigger with improved feel, removal of the integrated fixed sights, and adding a last-round bolt hold open on the 9mm version only.
Also added was the ability to rotate the barrel 90 degrees, which allows any mounted 12 o’clock optics or lights to rotate with the handguard to the side when folded. The barrel assembly can swivel either way during folding. Since the optic is rotating with the handguard and barrel assembly, there is no impact to zero when deployed. Previously on the Gen 1-2 versions, mounted optics would have prevented the SUB2K from folding flat. KelTec engineered a simple solution to the problem, and the rotating barrel works perfectly without being overly complex. An additional benefit of the design is that the swiveling barrel moves the optic into a more compact, backpack-friendly profile. Ergonomically, the unfolding and deployment process is very fast and simple. During testing, the SUB2K was able to be snapped into position and charged in under two seconds.
Simplicity Sells
In a world of $1,500-$2,500 PCCs and subcompact handguns with red-dot sights, it is refreshing to see that simplicity still sells. To put the price into context, the SUB2K is priced 30% less than a Glock Gen 5 MOS or the folding S&W FPC 9mm, 50% less than the Ruger LCC 5.7 Carbine, over a third the price of the FN 5.7 Pro pistol or a CMMG 5.7 Banshee. For many customers, the sub-$500 street price of a 100% American-made firearm is very attractive. Chambered in the capable 5.7x28, the SUB2K can serve as a home-defense, EDC, mid-sized-game hunting or a versatile truck and survival gun.
Industrial Style
The SUB2K was first and foremost designed as a minimalistic lightweight folding firearm. Compared to other PCCs dripping with artistic lines, free-floating handguards, ambi-everything and billet parts, the SUB2K feels more like industrial farm equipment, but that is not a negative. Though it feels stripped-down, the SUB2K still delivers everything you need in a solid, highly durable design, without features that would just add weight. Good engineering questions were clearly asked to keep weight and size to the absolute minimum without compromising durability.
A large majority of the parts are thick injection-molded Dupont polymers which further drive weight down to 4.25 pounds, which is a pound or two or about 30% lighter than any competing firearms. Considering the potential use cases of the SUB2K, the weight is a major sales point. The smooth thumb-operated left/right safety selector feels more like a shotgun safety, but it works.
The minimal design of the SUB2K stands out on a shelf with a retro-cool military sub-gun vibe. Customers do not seem to care about the industrial feel of the SUB2K and it still sells like crazy for KelTec. It remains an innovative, lightweight, durable and inexpensive platform that is cool, different and just works.
Spicy 5.7X28
Mechanically and functionally, the 5.7x28 version is the same as the 9mm version, with the omission of the last-round hold-open. The 5.7x28 SUB2K model accepts 20-round FN Pro-compatible magazines with a ProMag 20-round magazine included. KelTec offers 30-round optional magazines.
The SUB2K is part of the KelTec Peacekeepers program for asset protection, church security, school resource officers, and LEO needs where a fast-deploying, accurate and high-capacity bag gun could be valuable. Especially important for home defense or security teams, testing indicates that the 5.7x28 HP rounds would provide less (wall) pass-through compared to 9mm rounds — a smart option for protection in urban or security environments to reduce injuring innocent bystanders.
Features, Function and Performance
KelTec has worked through tuning and tweaking the SUB2K format with each subsequent generation, and the GEN 3 feels smoother and more refined. Everything from the molding quality to enhancing existing features has taken a major step forward.
Design simplicity delivers simple operation, stripping and cleaning that only requires a single disassembly pin to be removed for full field-stripping. The trigger has been upgraded to an aluminum bladed trigger with a predictable break. The safety selector is fast and natural to click rightward off safe with the grip thumb. The stock may be a bit minimalistic; however, it is loaded down with a surprising amount of features. The 1/2x28 muzzle threading works with compatible 5.7-rated rimfire suppressors well, and with the Rugged Oculus 5.7-rated rimfire suppressor, the report was extremely pleasant. Though inexpensive, the SUB2K is a tough little gun and can take significant abuse, with KelTec standing behind the firearm with a limited lifetime warranty.
With a bit of practice, the SUB2K can be launched into action with a loaded magazine from a folded position in one smooth sub-second action if the lock release is not engaged. Grab the buttstock and press the lock release with the thumb and simultaneously swivel the barrel assembly straight and down into locked position. Pull back on the charging handle and the gun is ready to fire. Notably, there are no automatic safeties, so if the gun is left with the safety off and magazine inserted, the SUB2K can go from folded to delivering first shots in about two seconds.
Testing ammunition included American Eagle, FN - Fiocchi HP, FN Personal Defense, Fiocchi Range Dynamics, Hornady Black, Hornady Critical Defense, and Speer Gold Dot. Reliability was perfect throughout testing without any failures, even when running mixed ammunition in the magazine, both suppressed and unsuppressed. Even suppressed, the recoil was delightfully light. The 5.7-rated rimfire Rugged Obsidian suppressor was used for testing in both long and short configurations. The 5.7x28 is a loud, snappy, high-pitched round that is often hard to suppress; however, the Rugged Obsidian did a good job of taming the report down to a very pleasant level.
Magpul backup sights and a Burris AR-F3 red-dot was added for testing, which netted reliable average 1/2-inch 25-yard accuracy and 1.25-inch 50-yard groups. Average 100-yard groups were under 3 inches; however, the non-magnified red-dot and lightweight format were likely the accuracy limiters. The higher-tier defensive ammo such as the FN, Speer and Hornady rounds did improve upon those groups, consistently delivering .75-inch 50-yard and 2-inch 100-yard groups. Based on the intent of the design, this was impressive accuracy for a folding rifle with a red-dot.
For the professional, personal protection, or the new or old shooters wanting a fun, unique and reliable option that can fill many roles, the sub-$500 SUB2K FN57 in 5.7x28 is a highly attractive firearm compared to its significantly more expensive competitors. The design is an intuitive format but does depart from AR standard controls. With the light-recoiling 5.7x28 and proven reliability, this is sure to be another hot-selling model from KelTec.
