FN PS90 vs. Kel-Tec CMR30


FN PS90 vs. Kel-Tec CMR30

FN PS90 has long been the most popular PDW derivative in the US, in part because most of its competitors are unavailable except as awkward stockless “pistols.” This summer, Kel-Tec CMR 30, a 22WMR autoloader, finally became available for sale.

In military use, rimfire arms had gone out of fashion by the 1870s, and the last of civilian rimfire calibers besides .22 vanished after the 1940s. Can the 22WMR gun take on PS90 in the self-defense niche?

CMR30's main claims to fame.
CMR30’s main claims to fame.

First, let’s look at the specifications:

Length, deployed26.2″30.6″
Length, collapsed26.2″22.7″
Weight, empty6.3lbs3.8lbs
Magazine Capacity5030
Ambidextrous controls?YesYes
Ejection directionDownRight
Accuracy (with magnified sights)1.5MOA1.5MOA
Ammunition cost, per round45c to 60c32c to 50c
Muzzle velocity, with 40gr bullets2100fps1950fps
Price$1200, retail$630, list

PS90 has a considerable edge in capacity and a 9% advantage in muzzle velocity. CMR30 has the advantage of much lower weight. Accuracy and felt recoil are comparable. Both guns sound suppress well. While CMR30 enjoys the advantage of magazine compatibility with PMR30, 22WMR isn’t all that efficient in the shorter barrel. PS90 and FN57 do not share magazines, but its ammunition is rather more efficient in pistols. PS90 magazine is substantially easier to load to full capacity. CMR30 magazine loads easily to 25, but it takes some effort to load up the remaining 5 without denting the rimfire brass.

Terminal effect from 5.7×28 ammunition is achieved by fragmentation or by de-stabilizing the spitzer bullet. It enjoys a slight advantage at longer ranges due to the more aerodynamic shape. Terminal effect of stubbier 22WMR bullets is achieved mainly by expansion, and they typically penetrate deeper. The two cartridges are roughly similar in gas volume, so most 22WMR suppressors can be used interchangeably with 5.7×28 suppressors. While rimfire cartridges are inferior in theory for reliability, I have experienced no 22WMR misfires with any brand or firearm. Zero ammunition-related problems over twenty years is a pretty good indicator of manufacturing quality.

While CMR30 is much cheaper to buy and to shoot than PS 90, the base model PS90 does come with an optical sight and primitive backup irons. The included sight is not very good, and I would recommend the tri-rail model with better optics. CMR30 comes with flip-up Magpul mechanical sights. The long top rail of CMR30 allows anything from a red dot to a high magnification varmint scope to be installed. For defensive use, a red dot or a low-magnification fixed scope would work best.

PS90 enjoys a 25 year track record and a wide adoption history. It proved itself as a robust and reliable weapon. CMR30 is brand new and just now starting to show up in retail stores. It enjoys certain improvements over its competitor, such as variable length of pull and much better, crisper trigger pull. The design is quite simple to produce, so there’s hope of seeing CMR30 in large numbers.¬†Given the similarity of performance on target, and the equally low recoil, it has a chance to become a popular defensive tool for people who require light weight and compact size.

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