Ruger Mark IV 22/45 Lite Review

I love shooting guns—all types of guns. At the top of my list is shooting a super-accurate 9mm Model 1911; blasting away with a smooth-operating .41 Magnum double-action revolver; reaching way out there with an ultra-accurate .338 Lapua bolt-action rifle; and plinking with a cool, fast-shooting .22 LR semiautomatic pistol. And when it comes to cool .22 LR semiautomatic pistols, none is cooler than Ruger’s Mark IV 22/45 Lite. The one I’ve been shooting is a red anodized pistol available exclusively from Davidson’s.

Before delving into the details of the Davidson’s Mark IV 22/45 Lite, I’ll remind you that Ruger’s 22/45 was originally designed to give rimfire shooters a pistol with the same grip angle as the classic Model 1911. The 22/45 was a Mark II series pistol first introduced in 1992. It was offered with 4.0-, 4.75-, 5.25-, and 5.5-inch barrels and a Zytel glass-filled nylon grip frame. You could have fixed or adjustable sights, and the original model had the grip panels molded into the grip frame. Later versions used removable grip panels, and in fact, standard Model 1911 grip panels fit. The 22/45 Lite came out in 2016, so it was a Mark III series pistol. It had the Zytel composite grip frame, removable black grip panels, and an aircraft-grade aluminum receiver/ventilated barrel shroud. The barrel length was 4.4 inches, and it had a threaded muzzle. The pistol weighed 23 ounces as compared to 28 ounces for an original 22/45 with a 4.75-inch barrel.

Enter the Mark IV

Ruger revamped its .22 LR semiautomatic pistols in 2017. The original version was born in 1949, and it went through several redesigns during its first 50 years, resulting in Mark I (1951), Mark II (1982), and Mark III (2005) models. Then in 2017, the Mark IV series was introduced. It’s the culmination of almost 70 years of development. The most significant revision was the easy one-button takedown system. Previous pistols had a takedown latch located in the backstrap of the grip frame, which required inserting your fingernail or the tip of a tool into a shallow recess and pulling the lever toward the rear. Then the latch had to be pulled out toward the rear, swinging out the mainspring housing and turning it up, and then pulling the housing straight down to withdraw the boltstop pin, which was attached to the top of the housing. The bolt could be removed from the rear of the barrel extension. The parts of the bolt assembly could be disassembled, and the barrel/receiver unit could be pushed forward off the frame.

Disassembly wasn’t too difficult, but reassembly was darn tricky. When I worked at Gil Hebard Guns from 1977 until 1992, we had numerous customers bring in their disassembled Ruger .22 auto pistols for us to put back together for them. Gil was adept at it, and eventually I became pretty good at it, too. The trouble most customers had was getting the hammerstrut in the proper position.

Here’s how the process is supposed to go. First, return the barrel/receiver unit to its proper position on the frame with the boltstop pin hole properly aligned with the frame. It may be necessary to tap the barrel with a non-marring hammer to line it up. Reinsert the bolt assembly. Insert the boltstop pin, and with the hammer in the “fired” position, tilt the pistol so the hammerstrut drops against the inside of the mainspring housing. Swing the housing into the frame. If the housing locks in place but the bolt won’t retract, the strut has missed its correct position and the housing will need to be opened and reinserted.

With the Mark IV series guns, the engineers completely redesigned the internal parts to eliminate the confusion. The critical component is the takedown button on the rear of the receiver underneath the bolt. With the pistol unloaded, the magazine removed, and the safety engaged, simply press the button, and the bolt assembly and barrel tip forward. They can be easily removed from the grip frame. It’s fast and slick. Reassembly is just as quick and easy.

The Mark IV thumb safety and boltstop were also redesigned. The safety is now ambidextrous, and the boltstop is relocated in an-easy-to-operate position.

Davidson Ruger Mark IV 22/45 Lite

Davidson’s Mark IV 22/45 Lite has a 4.4-inch barrel with a threaded, recessed, and precision crowned muzzle. Muzzle diameter just behind the threads is 0.99 inch. The receiver/barrel shroud wears a striking red-anodized finish. The red color is exclusive to Davidson’s. Or, if you prefer, you can get a magenta-anodized and an OD-green-anodized finish from Davidson’s. And, of course, you can get a standard-finished all-black 22/45 Lite, too.

The 22/45 Lite’s trigger does not have an overtravel stop screw, and my sample pistol had a bit of overtravel. My pistol’s trigger pull averaged 5 pounds, 12 ounces over a series of five measurements with an RCBS trigger pull scale, and there was very little variance between measurements. Take-up was firm and consistent, but it was longer than I prefer.

---

The front of the 22/45 Lite’s grip frame is striated, and the backstrap is checkered. The grip panels are checkered and bear the Ruger logo.

The boltstop is located on the left side of the receiver, and it is easy to reach and easy to operate. The thumb safety is ambidextrous, but it can be converted to left-side-only. It is larger and easier to use than the old-style safety. I wasn’t a fan of the old-style sliding-button safety lever because I could never manipulate it easily. I think the Mark IV safety is much easier to operate.

Like I said earlier, the 22/45 Lite comes with an optics rail installed. I put it to good use by mounting an Aimpoint Micro H-2 red-dot optic. According to Aimpoint, the Micro H-2 was developed for shooting with both eyes open. The Micro H-2 is lightweight (4.8 ounces with lens covers) but rugged, and it can be used on shotguns, rifles, and handguns.

The 1X Micro H-2 is non-magnifying and parallax free, and it is fully adjustable for windage and elevation. The top of the protective caps fit into holes on the adjustment screws, and each click of the adjustment screws corresponds to a 0.5-inch movement of the point of impact at 100 yards.

The optic features advanced lenses and cutting-edge lens coatings for excellent light transmission. The unit comes with a built-in Weaver/Picatinny-style base. The Micro H-2 also comes with clear flip-up lens covers, and the aluminum housing is reinforced for improved ruggedness.

It’s powered by one CR2032 battery, and its low-power-consumption Advanced Circuit Efficiency Technology allows 50,000 hours (over five years) of constant operation with one battery. The dot has 12 brightness settings, allowing it to be used in varying low-light and daylight conditions. It’s offered with two dot sizes (2 and 4 MOA). Mine has the 2-MOA dot. The Micro H-2 is fully waterproof, and according to Aimpoint, it has become the company’s most popular red-dot sight with hunters, competition shooters, and sport shooters.

The 22/45 Lite also comes with sights. The rear is an all-black adjustable target-style sight made of steel. The front sight is a black post, and it is attached to the barrel with a screw. The notch in the rear sight is 0.111 inch wide, and the front sight is 0.121 inch thick.

The magazine release button is located Model-1911-style, and magazines drop free when the release is activated. The pistol comes with two 10-round magazines.

Shooting the Ruger Mark IV 22/45 Lite

My all-time favorite .22 LR pistol has always been the old High Standard Supermatic Citation with the military grip angle. I sold my High Standard Citations more than 30 years ago, but I remember how well they shot. Those High Standards had a push-button takedown setup that made switching barrels extremely easy, and match-grade aftermarket barrels were available from several quality barrelmakers. I had a couple of extra barrels for my pistols. I also like the recently introduced Smith & Wesson SW22 Victory pistol a lot, mainly because of its easy-to-switch barrels. And although the 22/45 Lite is not a switch-barrel gun, I like it, too. My sample shot well, and its lighter weight makes it easy to pack as a trail and woods gun.

Compared to my old High Standard Citations and my SW22 Victory, the 22/45 Lite wasn’t as accurate during my shooting sessions, but it was definitely accurate enough to serve well as a plinker and a woods gun. On top of that—and more importantly—it functioned perfectly. I put more than 250 rounds through it and didn’t have a single failure to feed, extract, or eject.

The accompanying chart shows the average accuracies for five, five-shot groups fired with 10 factory loads from a sandbag benchrest at 25 yards. Overall average accuracy was 1.87 inches. My best accuracy came with the Eley Pistol Match 40-grain RN ammo.

I am a mediocre shooter at best, so the 22/45 Lite is most certainly capable of better accuracy in the hands of a better shooter. The pistol’s good shootability, great features, and light weight make it a top choice, and handgunners who enjoy shooting Model 1911s will surely appreciate that its grip frame mimics that of “Old Slabsides.” You might say the Ruger Mark IV 22/45 Lite is a plinker with purpose.