Florida-based KelTec this week debuted the latest caliber offering in the company's extremely popular SUB2000 carbine series. 

Introduced in 2001 with a host of different common magazine well choices, the SUB2000's biggest claim to fame is that it folds neatly in half for storage. Evolving into a second and currently third generation since then, the pistol-caliber carbine had previously been offered in 9mm or .40 S&W. Well, until now, at least. 

The newest SUB2000 runs FN's 5.7x28mm and uses common 20 and 30-round FN Five-seveN pattern magazines. It can also accept 55-round drums. Running from a blowback action, standard features include integrated M-LOK and Picatinny rails for accessories and optics. It is also threaded (1/2x28 TPI) for easy suppressor use. 

The move follows in KelTec's recent design history as the company has been introducing several different 5.7 platforms over the past few years such as the P50 Sports Utility Pistol and R50 Sports Utility Rifles, the latter in multiple barrel lengths.  

The MSRP on the new KelTec SUB2000 Gen 3 in 5.7 is $511. Speaking of which, 5.11 probably offers a ton of "I'm not carrying a folded carbine in a backpack" backpacks that will fit it. 

When speaking to that asking price, the new SUB2000 easily beats everything else in the semi-auto 5.7 carbine space, coming in cheaper than the CMMG Resolute and MK4, FN's PS90, Ruger's LC Carbine, and even KelTec's own R50. 

As Fiocchi last week nominated the cartridge with SAAMI for U.S. standardization, you can expect to see more of the 5.7 soon. Likewise, ammo availability is probably at an all-time high for this once-rare little round and prices have dropped from over $1 apiece to more like 50 cents a pop if buying in bulk.