Gear

Ares Defense recently introduced a conversion unit for Ruger MK-I, MK-II, MK-III and 22/45 pistols that changes the popular pistol into a lightweight, .22-caliber carbine. The conversion replaces the tubular receiver of the Ruger, and utilizes the Ruger's grip handle, bolt assembly and magazines. As the tubular receiver of the Ruger is the serial-numbered part for FFL purposes, the Ares RCU is considered a firearm.

Converting the pistol is simply a matter of removing its magazine, lowering the hammer, flicking the takedown latch open on the mainspring housing and removing the grip handle and bolt from the Ruger receiver. Those parts are then reassembled on the RCU in reverse order and viola, you have a blow-back operated .22-caliber carbine. If you've ever taken apart a Ruger 22 to this level you're probably familiar with the aggravation you can encounter trying to reassemble it correctly. Do it wrong, and you can't pull the bolt all the way back. Here's a little trick for putting the Ruger back together that's applicable to the RCU and will save you that frustration.

Before attaching the pistol grip, make sure the hammer is in the cocked position. Insert the bolt, attach the grip handle, rotate the muzzle down, and pull the trigger to lower the hammer to the fired position while making sure the hammer strut stays pointed down the back of the backstrap. Next, fully insert only the bolt stop part of the mainspring housing and rotate the gun's muzzle up while closing the mainspring housing and then lock its latch. Rotating the muzzle up that way causes the hammer strut to find its way nicely into its little recess in the mainspring housing.

Inside the RCU's receiver, a 16 1/4-inch barrel locks into the Ruger's grip at the rear, and is centered and secured at its front by a threaded lock ring. A full-length MIL-STD 1913 top rail allows mounting of sight accessories. The sample unit came equipped with a Trijicon RM05 amber dot sight and optional Knight's armament Folding Front and 300-Meter Backup folding rear. With these iron sights, you adjust elevation by way of the front sight post just like you would on a standard AR-15 front sight while the rear sight is click-adjustable for windage. The rear sight also has a polymer reduced aperture insert for more precise aiming. Arguably 300 meters is a bit optimistic for a .22 Rimfire, especially in a carbine format, so if you select these iron sights you're probably better off to simply pop out the reduced aperture insert which leaves you with a large ghost ring type of rear sight for fast close-range target acquisition.

A telescoping wire stock is integrated into the top rail. Deploying it is simply a matter of grasping the butt and pulling the stock rearward where it locks in place providing a length of pull of 13 3/4 inches. To collapse, there's a round button at the rear of the top rail that you push to the side while pushing the stock back to the closed position. There are no intermediate stock positions, only fully extended and fully collapsed for overall lengths of  30 1/2 inches, and 26 1/4 inches, respectively.