I just had to field test the LCR in 9mm to view if it met or exceeded the effectiveness of your LCR I by now very own. Practically all of my handguns and carry guns are in 9mm caliber, which I favor.† NOTE: The receiver-mounted, Picatinny-style rail is developed to accommodate most optics and optic mounts intended to be used with Picatinny/ MIL-S