Meet the Ruger Mark III: A Guide to Disassembly and Reassembly

For starters, the Mark III isn’t the same on the outside as the familiar Mark I and II. Compare the magazine latch and grip configurations with those of its earlier brethren. Inside, several new wrin kles are present for which patents are pending. These include the internal lock, loaded-chamber indicator, and magazine disconnect. The pistol featured here is the Standard Model.

Variations on its theme are the Government Target Model with a heavy laser-targeted barrel, the Competition Model with a slab-sided heavy barrel, and the 22/45. The 22/45 has 22 pistols, the exterior differences alone are enough to tip you off that there are significant differences in Ruger’s new offering. its own, dedicated magazine sold only for it and no other Mark III. Since it differs so greatly from the other Mark III pistols, it will be addressed separately in a future article.

And while I’m thinking of it, I should point out that no other Ruger .22 auto magazine can be used in a Mark III. It won’t function the bolt stop or the magazine disconnect. The disconnect is anew feature that keeps the trigger from being pulled if the magazine is removed. Another new feature is the loaded-chamber indicator. When the chamber is empty, the indicator lies flush with the left side of the barrel/ receiver assembly.

If a cartridge remains chambered, the indicator protrudes, showing ared dot and the word "Loaded." The third newcomer is the internal lock, a key-operated device that secures the manual safety in the "S" position. To activate the lock, the pistol must be cocked with the safety engaged. The key supplied with the pistol is placed in the keyway located just under the manual safety cutout in the frame and is rotated clockwise until it stops.

The safety can’t be disengaged and though the bolt can still be retracted to clear the chamber, the rest of the action is frozen. Before the safety can be deactivated, the key is inserted and turned counterclockwise until it stops. Basic Disassembly Mark III pistols have been designed to be field stripped without the use of exotic tools. Handy to have available, however, particularly with brand new pistols, area rubber or leather mallet, a 1/8- to 1/4-inch-diameter wooden dowel, and a husky paper clip.

As usual, start by making sure the gun is empty. Fully insert an empty magazine and disengage the internal lock if necessary. Place the manual safety on "F." Pull the trigger to make sure the hammer has fallen. It has to be in its fired, or forward, position for the pistol to be disassembled. Remove the magazine, insert the paper clip into the oval recess in the mainspring housing, and work the clip in behind the housing latch. Take a

Figure 1. firm hold on the pistol elsewhere to swing the latch outward and down, then use it as a handle to pivot the housing away from the grip frame. Regrip the latch/housing assembly and pull it downward to remove the bolt-stop pin. On new pistols, it may be necessary to tap the top of the bolt-stop pin that extends from the back of the receiver with a wooden dowel during the removal process. Reinsert the empty magazine, tilt the muzzle at least 45 degrees upward and pull the trigger.

The bolt should slide out on its own, but if it doesn’t, a little encouragement with finger pressure will pull it from the receiver. A rap on the rear of the receiver will start the barrel/receiver assembly off the frame. Basic Reassembly The manual safety is on "F." Keep your fingers off the trigger and push the hammer down to its cocked position (Figure 1). There are a couple of reasons why you may not be able to cock the hammer.

The first is that the hammer strut has become trapped behind the cross pin (see Figure 2). In this case, lift the hammer and move the strut in front of the cross pin. The other possibility is that the hammer has rotated too far forward, which makes it difficult to rotate backwards. Don’t force it. Inserting an empty magazine fully will allow it to be cocked. Then remove the magazine. Hammer receiver assembly to the rear until it stops.

Ideally, under hand pressure alone, the assembly will come to a halt with the end of the receiver slightly overhanging the frame. In a less-than-ideal circumstance, the pistol should be placed muzzle down on a protected surface and the rear Before reuniting the barrel/receiver assembly to the grip frame, make certain the loaded-chamber indicator is still housed in the receiver. Place the assembly atop the frame so the square recess on its underside corresponds to the square lug on the frame.

Engage the two elements and push the barrel/ Figure 2. Hammer Strut Crosspin of the frame carefully tapped with your soft-face mallet just below the receiver. The empty magazine goes back in the pistol, the muzzle is tilted straight up, and the trigger is pulled. If gravity doesn’t serve to return the hammer to a cocked state, reach into the back end of the receiver, push it down, and remove the magazine.

Don’t reinstall the bolt in the receiver until you’ve checked to see that the firing-pin stop pin (#18) is present. If that part is missing, the first time the pistol is fired on an assembled gun the firing pin will put an irreparable dent on the chamber perimeter. Scratch one Ruger Mark III. Having eliminated that fatal scenario with your "pin-is-in" check, slide the bolt with the recoil spring upward fully into the receiver. Once again, back in with the empty magazine, point the muzzle down, and pull the trigger.

The hammer should release to its fired position. It didn’t? Okay, partially retract the bolt, push the hammer forward through the rear frame slot, and remove the magazine. Judging from the number of incorrectly or incompletely assembled Ruger .22 pistols sent back to the factory for "repair," this is the number one problem: the bolt pin/ mainspring housing. Because a "loosey-goosey" pistol results in a sadly inaccurate pistol, Ruger builds its .22s tight.

The boltstop pin is a tight fit through the bolt and the receiver. The barrel-lug engagement is tight. They have to be or the guns couldn’t produce a decent group even when fired from a Ransom Rest. Anything you do, such as polishing the bolt-stop pin so it will install more easily, must be performed with extreme care. Otherwise, you’ll be creating slop, and slop is the last thing you want to hand back to a customer.

That having been said, point the muzzle down, grasp the bolt stop/ mainspring housing as a unit, and insert the stop pin until it protrudes above the receiver ( Figure 3). Your safe mallet can be used on the bottom of the housing to nudge the pin into

Ruger Mark III .22 Semi-Auto Pistol (Specifications subject to change without notice) 1 Barrel/Receiver Assembly* 2 Front Sight 3 Front Sight Screw 4 Barrel/Receiver Filler Screws (3) 5 Loaded Chamber Indicator 6 Loaded Chamber Indicator Spring 7 Loaded Chamber Indicator Pin 8 Rear Sight Bottom 9 Rear Sight Pivot Pin 10 Rear Sight Elevation Spring (2) 11 Rear Sight Base 12 Rear Sight Elevation Screw 13 Rear Sight Blade 14 Rear Sight Windage Spring 15 Rear Sight Windage Adjustment Screw 16 Rear Sight Base Set Screw 17 Bolt, Only 18 Firing Pin Stop Pin 19 Rebound Spring 20 Rebound Spring Support 21 Firing Pin 22 Recoil Spring Assembly 23 Extractor Spring 24 Extractor Plunger 25 Extractor 26 Grip Frame w/Trigger Guard* 27 Trigger 28 Trigger Spring 29 Trigger Spring Plunger 30 Trigger Pivot Retainer 31 Bolt Stop Assembly 32 Bolt Stop Plunger 33 Bolt Stop Plunger Spring 34 Trigger Pivot Pin 35 Safety Assembly, Complete* 36 Hammer Assembly, Complete* 37 Magazine Disconnector Spring 38 Magazine Disconnector 39 Disconnector Assembly* 40 Hammer Bushing 41 Sear Spring 42 Sear* 43 Bolt Stop Thumb Piece 44 Hammer Pin 45 Magazine Latch 46 Magazine Latch Spring 47 Magazine Latch Spring Plunger 48 Magazine Latch Screw 49 Sear Pin 50 Sear Spring Pin 51 Magazine Latch Pin (2 required) 52 Mainspring Housing Assembly 53 Lock Pin 54 Spring Back-up Pin 55 Detent Plunger Lock 56 Lock Plunger Detent Spring 57 Hammer Spring Plunger 58 Hammer Spring 59 Housing Latch Detent Ball 60 Housing Latch 61 Housing Latch Pin 62 Grip Frame Filler Front and rear sights for Target Models are not adaptable to Standard Models. 63 Grip Panel, Left 64 Grip Panel, Right 65 Grip Panel Screw (2) 66 Magazine, Complete 67 Internal Lock Key *Indicates factory fitting required.

Figure 3. Figure 1. Push up until bolt stop pin protrudes here. place, but don’t swing the housing into the grip frame just yet. Point the muzzle up and let the housing drop down. You ought to be able to see the tip of the hammer strut. The strut must seat in the oval recess on the housing as the housing is swung back into the grip frame. Got it? Good. Now hold the trigger to the rear and swing in the housing.

The latch can then be closed and, if all internal parts are aligned, you should feel some spring resistance before it snaps shut. To see whether or not you have an internal alignment problem, pull the bolt to the rear. If it fails to fully open, swing out the latch, remove the bolt pin/mainspring assembly and reinstall it.

If retracing those steps becomse necessary, keep the following in mind: One, if the mainspring housing pulls out of the pistol as you swing it inward, the barrel/receiver isn’t seated properly to the rear on the frame; two, the hammer must be in its vertical, fired, position as the housing is shut or else the housing will be excessively hard to close; and three, the hammer strut must be properly seated in the housing.

To make your final basic reassembly check, insert the empty magazine, hand cycle the bolt, and pull the trigger. Detailed Disassembly Remove the grips from both sides of the frame and back out the magazine latch screw (#48). The latch (#45), latch spring (#46), and latch-spring plunger (#47) can now be pulled out as a unit with your fingers. Drift or push the hammer pin (#44) from right to left.

If you turn the frame upside down at this point, the complete hammer assembly (#36), magazine disconnector spring (#37), magazine disconnector (#38), hammer bushing (#40), and bolt-stop thumb piece (#43) will fall out on your bench. I hope you took along look at how they were originally installed before you removed the hammer pin. And there’s been a design change in the magazine disconnector. It’s no longer like the one shown in the schematic.

Its back end has been extended to keep the disconnector spring from being overstressed. Now push the manual safety (#35) into the frame and catch it as it drops out. The sear pin (#49) can be drifted in either direction to release the sear (#42) and sear spring (#41). Catch them, too.

The disconnector assembly (#39), trigger (#27), trigger spring (#28), trigger-spring plunger (#29), bolt-stop assembly (#31), bolt-stop plunger (#32), and plunger spring (#33) will all free up when the trigger-pivot pin (#34) is drifted out in either direction. Wait a second. Before drifting the trigger pivot, you have to depress its retaining spring (#30). Aside from that, the trigger assembly on the Mark III is the same as that of the Mark II.

So is the bolt assembly. (For fully disassembling these components, you can follow the instructions that appear in the NRA Guide to Firearms Assembly or Gun Digest’s book on automatic pistols.) While you’re working on a Mark III bolt, however, you’ll notice it has a slot on its front left side. It’s there to accommodate the loaded-chamber indicator. This brings up another design change. The indicator in the pistol shown here bore little resemblance to the indicator in the schematic.

The indicator (#5) on new pistols has a polymer rather than a steel body, a metal tab (not shown), and two springs (#6). These are held in by an indicator pin (#7) and you use no tool to get it out. Merely take a firm grip on the barrel close-in to the receiver and tap the receiver bottom side down on your bench a few times. The pin will start to drift itself out. Frequently, it will self-drift enough for you to remove the indicator assembly.

If not, you can extract the pin a little further with your fingers, but don’t pull it all the way out. That way, when reinstalling the indicator assembly, after you have placed it in its slot and aligned the pin hole, you merely have to push the pin back up to re-secure the indicator. This leaves the sear-spring pin (#50) and magazine-latch pins (#51) still in the frame.

I prefer to let the sear-spring pin remain untouched and can think of no reason to remove the latch pins unless the latch itself (#62) has been damaged to the point of replacement. If it ain’t broke, don’t fix it. Know what I mean? If the bolt were to be installed without this pin, upon firing, irreparable damage would render the pistol useless.

The internal lock keyway (C) is always unobstructed. For a totally different reason—call it covering my posterior—I’ve not included disassembly of the mainspring assembly. With the addition of the internal lock, it has become a vital safety feature and my rigid policy is never to defeat or tamper with the safeties on any gun. Chicken? Maybe, but it has spared me lawsuits and jury awards I don’t have the bucks to pay.

Reassembly Tips It’s impossible for me to show you detailed, interior photos of a Mark III grip frame. I don’t own and can’t afford the surgically small camera equipment necessary to do so. Therefore, I must rely upon your natural curiosity, your use of a high-intensity pen light and magnification to make your own examinations. I suggest these be made after each disassembly step is taken, because with each step, more is revealed.

For example, the trigger-pivot retainer, having thankfully done away with the nightmarish little E-clip trigger keeper on Mark I pistols, wears a small hook at one end. That hook fits under a pin, which is a permanent part of the frame and cannot be seen with the trigger assembly in place. The forward extension of the retainer fits in a slot on the lower right-hand side of the frame’s barrel lug. The slot is masked by parts #31, 32, and 33.

You’ll want to make and use a slave pin, rounded at one end, which almost matches the hammer pin in diameter. Install the sear, sear spring, and sear pin. After that, position the manual safety in the frame and start in the hammer pin to retain it. Rotate the sear forward to lock it down. Position the disconnector in the frame, and start in the hammer bushing from the right. Spear the magazine disconnect and spring on the bushing, and start your slave pin through to hold them in place.

The hook at the top of the spring fits in a crescent area atop the disconnect. Add the hammer and tilt it forward. The tail of the magazine-disconnect spring has to eventually fit down behind the sear-spring stop pin. Doing that is the tricky part of reassembly, since you 22 pistols. The tool is described more fully in the text. B C Ahave to do the maneuvering after all the upside components you’ve been working with are in place.

I ended up using a length of small-diameter drill rod with a notch cut at one end to push that spring around, and I don’t suppose you’ll have any more trouble doing it than I did. But "tedious it is," as Yoda the Master Jedi would say. After breathing a sigh of relief, rotate the hammer back to its cocked position and allow the disconnector to get on top of the sear. Push out the hammer pivot with your slave pin.

Position the bolt on top of the top thumb piece over the slave pin, use the hammer pivot to push out the slave pin, and seat the pivot against the thumb piece. Reinstall the magazine-latch assembly, latch screw, frame grips, and function test the pistol with dummy rounds. One afterthought: The odd-looking pliers pictured here is a made-inhouse tool that assembly workers use to install the sear and sear spring simultaneously.

The tips of the pliers have been rounded and their faces milled out to match the shape of the sear body. A slot has been cut on the top side of the pliers to accommodate the sear spring. In use, the sear is held between the milled jaws, the spring placed in the slot, the pliers inserted into the frame down to the sear-pin hole, and the pin is pushed through. Ruger lent me one to work with and to show to you. It’s a gem. Feel free to make one of your own. ■