Inevitably, Kel-Tec’s new .22 Magnum (WMR) chambered PMR-30 pistol will be compared to the FN Five-seveN pistol which fires the ballistically similar 5.7x28mm cartridge. If people are not saying it now, they will be soon saying that the .22 Magnum is the same as the 5.7x28mm. I used to say the same thing. It turns out that this is far from the truth.
This does not mean that the .22 WMR is not a good cartridge. It simply means that the 5.7mm is optimized to be fired from a pistol, rather than the slower burning .22 WMR loads which are designed to be fired from a rifle.
UPDATE: Added correct link to specs on Kel-Tec’s website : http://www.kel-tec-cnc.com/downloads/SHOT2010_preview_keltec_PMR-30.pdf [PDF Link]
I assume that the 5.8mm load mentioned above it a hot load. I also assume that Kel-Tec will be publishing the results of the best performing ammunition they could find ↩