THE UNOFFICIAL OPERATOR MANUAL for the RUGER MK II by Richard M. Bash Combat Arms 2869 Grove Way Castro Valley, California 94546 Telephone (415) 538-6544 September, 1988 . - MANDATORY USE OF FACTORY MANUAL WARNING - We live in an age when lawyers are suing everyone for almost anything under the sun. Therefore, it is necessary to advise you, the reader, that this manual in no way replaces or supersedes information or instructions from Sturm, Ruger & Co. Inc. In the event of a conflict between the information contained herein and the information in official Ruger publications, it is the Ruger publication which takes precedence. Combat Arms will be happy to answer any questions you may have but the final authority is always the information from Sturm, Ruger & Co. Inc. Assembly and Disassembly of The Ruger Mark II Pistol APPLICABILITY The following applies to all models of the Ruger Mark II .22 caliber pistol, including the Government Model, as manufactured by Sturm, Ruger & Company, Inc. (hereinafter referred to as "Ruger"). INITIAL INSPECTION Upon initial receipt of the pistol, it should be inspected and cleaned to assure complete, undamaged delivery and reliable, safe functioning. DESCRIPTION The Ruger Mark II automatic pistol is a .22 caliber rimfire, 10 shot magazine fed, semiautomatic, recoil (also called "blowback") operated weapon, chambered for the .22 caliber Long Rifle (LR) cartridge. This model includes the following features with which the user should be thoroughly familiar. BOLT The bolt can be manually retracted to chamber a cartridge from a loaded magazine or to clear the pistol by pulling the bolt ears to their rearmost position. Releasing the bolt ears will cause the bolt to fly forward under spring pressure. BOLT STOP ASSEMBLY The bolt stop assembly holds the bolt in a rearward position. It may be actuated either manually or automatically. Whenever there is an empty magazine assembly in the pistol, and the bolt moves to its rearmost position, the magazine follower button automatically actuates the bolt stop to hold the bolt rearward. This will occur regardless of whether the bolt is moved rearward when the last round is fired or by manual retraction. If there is a loaded magazine in the pistol or if there is no magazine in the pistol, the user may actuate the bolt stop by manually retracting the bolt and pushing up on the bolt stop thumbpiece. To release the bolt from the bolt stop when there is a loaded magazine or no magazine in the pistol, merely pull the bolt ears to the rearmost position and release. If there is an empty magazine in the pistol, the bolt can be released by pulling the bolt ears rearward and manually depressing the bolt stop thumbpiece to allow the bolt to return to its forward position. - LOADED MAGAZINE WARNING - The bolt stop is spring loaded to move downward. Therefore, when there is a loaded magazine in the pistol and the pistol is jarred to the extent that the bolt moves rearward, the bolt will fly forward and chamber a cartridge. For this reason the safety of the pistol should always be in the on ("S") safe position except when the user is positioned to fire the pistol at a selected target. SAFETY When the safety assembly is in its uppermost ("S") safe position, the sear is locked and the pistol will not fire. When the safety is in its lower ("F") fire position, the pistol will fire! The safety can only be moved to its safe ("S") position when the hammer is cocked. Therefore, the safety serves as a cocking indicator. The bolt can be manually retracted and released when the safety is on ("S"). This feature allows the pistol to be loaded or unloaded and allows a cartridge to be chambered when the safety is on ("S"). The safety should be on ("S") at all times except when the user is deliberately positioned to fire at a selected target. TARGET MODEL TRIGGER SCREW The trigger assembly contains an overtravel screw on the target models. This screw is adjusted at the Ruger factory for proper functioning and should not need adjustment. The purpose of the overtravel screw is to limit the distance the trigger moves after the hammer falls. Improper adjustment of this screw results in either (a) the screw being screwed out so far that the hammer will not fall or (b) the screw will not be screwed in far enough and thereby allowing excess overtravel to the detriment of accuracy. Adjustment of this trigger overtravel screw, if required, should only be performed by a qualified armorer. MAGAZINE The 10 shot magazine assembly is readily identified by the removable plastic base decorated with a silver "eagle" and is designated by Ruger as the M10 magazine. This is the only Ruger factory magazine that should be used with the Mark II pistol because it is the only Ruger magazine which will correctly function the bolt stop. Use of non-factory magazines is not recommended by Ruger. However, the experience at Combat Arms has been that the 12 round magazine from Ram-Line, Inc. (part number MAK 1210) has shown that this magazine is the ONLY non-factory magazine that consistently works in the Ruger MK II pistol. The Ram-Line, Inc. MAK 1210 magazine also has a life time warranty! It costs $12.95 (as of this writing) and is a stock item at Combat Arms. However, use of a magazine made by other than Ruger may void Ruger's warranty. - MAGAZINE USE WARNING - Do not use the Ruger 9 shot magazines (identified by their non-removable bases) designed for earlier model Ruger pistols (Mark I, etc.) in Mark II pistols. Do not use Ruger 10 round M10 magazines in Ruger pistols other than the Mark II. - MAGAZINE FOLLOWER USE CAUTION - Never lower the magazine follower button on the magazine and then permit it to snap upward. Always "ride" the button up and down with your thumb to avoid damage to the magazine and possible discharge of .22 caliber rimfire cartridges in the magazine. - WARNING - The Mark II pistol will fire when a live round is chambered, regardless of whether or not a magazine is installed in the pistol. Removing the magazine does not unload the pistol. To unload the pistol, FIRST REMOVE THE MAGAZINE, THEN PULL THE BOLT FULLY TO THE REAR AND EJECT THE CARTRIDGE. DO NOT ASSUME THAT THE CHAMBER IS EMPTY; ALWAYS VISUALLY INSPECT THE CHAMBER EVERY TIME YOU HANDLE THE PISTOL. THE SAFETY SHOULD ALWAYS BE ON ("S") WHEN UNLOADING THE PISTOL. Ammunition The Ruger Mark II automatic pistol is chambered for the caliber .22 Long Rifle cartridge, standard or high velocity. Use only ammunition manufactured to U.S. industry standards or to U.S. military specifications. Do not attempt to load .22 Long, .22 Short or any other type of .22 caliber ammunition into the magazine or the chamber of the Ruger Mark II pistol. - AMMUNITION WARNING - The Ruger Mark II pistol may be damaged and death or serious injury may occur to the user or other persons from any condition which contributes to the generation of excessive pressure or the uncontrolled release of gas within the Mark II pistol. These conditions can be caused by barrel or chamber obstructions, propellant powder overloads or by defective, incorrect or improperly loaded and assembled cartridge components. The relatively thin, soft metal used in .22 caliber rimfire cartridges makes burst cartridge case heads a common occurrence in firearms of this caliber. Therefore shooting glasses should ALWAYS be worn when firing the Mark II pistol. - BARREL OBSTRUCTION WARNING - Before loading or firing the pistol, examine the barrel to be certain that it is clear and unobstructed. Firing the Mark II pistol with any obstruction in the barrel - even a heavy coating of oil or even drops of water - may result in damage to the pistol and injury to the user or persons nearby. A misfire or unusual report on firing is always a signal to cease firing immediately and examine the chamber and bore. If there is any type of obstruction - even a partial obstruction - the user must clear the obstruction with a cleaning rod and bore brush before firing the Mark II pistol. SPECIFICATIONS Weight Without magazine 2.7 pounds With empty magazine 2.8 pounds With full M10 magazine 2.9 pounds Length Overall 11.125 inches Barrel 6.875 inches Sights Sight radius (on 6.875 inch barrel) 9.281 inches Adjustment « inch per click at 25 yards Mechanical features Rifling 6 grooves Twist 1 turn in 15 inches (right hand twist) Trigger pull Approximately 50 ounces Magazine capacity Ruger M10 magazine 10 cartridges Caliber .22 Long Rifle only Disassembling the Ruger Mark II - LOADED WEAPON WARNING - Never clean, lubricate, disassemble, assemble or work on the Mark II pistol while it is loaded. Keep all loaded ammunition away from the cleaning area. - MUZZLE SAFETY WARNING - Keep the muzzle of the Ruger Mark II pistol pointed in a safe direction at all times during the disassembly and assembly of this pistol. REMOVAL OF THE MAGAZINE Place the safety on ("S"). With the thumb of either hand, push the knurled magazine catch rearward and pull the magazine assembly down out of the lower receiver by its grooved base. Remove all cartridges from the magazine by pushing them forward and allowing them to pop out. CHECK CHAMBER FOR NO CARTRIDGES With the pistol pointed in a safe direction and YOUR FINGER OFF THE TRIGGER, grasp the bolt ears with the thumb and index finger and pull the bolt fully rearward. Make certain the Ruger Mark II is empty! Visually verify that no ammunition is in the chamber. Release the bolt ears and allow the bolt to fly forward. UNCOCK THE HAMMER The safety must be off ("F") and the pistol uncocked to disassemble the Mark II. Point the weapon in a safe direction and, with the pistol unloaded, pull the trigger. The hammer must be uncocked to relieve the pressure on the mainspring before the weapon can be disassembled. UNLATCHING THE MAINSPRING HOUSING The perfect "tool" to use for raising the mainspring housing latch is a lady's bobby pin. Combat Arms has found nothing better for disassembling the Ruger Mark II than this. Using your fingernails will just result in broken nails. If you use a screwdriver, you risk scratching the pistol. Some users have reported that they use a piece of string looped over the latch. Using the bobby pin, lift the mainspring housing latch UP out of the handgrip as far as it will go, much like opening the blade of a pocket knife. This will bring the latch to an approximate 90ø angle to the handgrip. INITIALLY POSITIONING THE HAMMER STRUT Point the empty pistol straight up and pull the trigger in order to make the hammer fall to its rearmost position. REMOVE THE MAINSPRING HOUSING ASSEMBLY Pull straight DOWN on the mainspring housing until the mainspring housing pin clears its hole in the top of the receiver. With new pistols it may be necessary to lightly tap (with a plastic, rubber or wooden hammer) on the end of the mainspring housing pin which protrudes through the top of the upper receiver assembly while pulling downward on the mainspring housing. The mainspring housing is now able to be removed from the pistol. POSITIONING THE HAMMER FORWARD Point the Mark II muzzle DOWN and pull the trigger. REPOSITIONING THE HAMMER STRUT Now raise the empty pistol vertically and point it straight up until you hear a click. This click tells you that the hammer strut has fallen back. If you do not hear the click, go back to the previous step, entitled POSITIONING THE HAMMER FORWARD. REMOVAL OF THE BOLT ASSEMBLY You can now pull the bolt out of the receiver by pulling on the bolt ears while continuing to point the pistol at the ceiling. If the bolt will not come out, then the hammer is not positioned aft; go back two steps to POSITIONING THE HAMMER FORWARD. REMOVAL OF THE UPPER RECEIVER ASSEMBLY Grasp the lower receiver and hold the bolt stop thumbpiece UP. Hold the pistol over a padded work surface which will receive the upper receiver when it is removed. Tap the rear of the upper receiver with a plastic, rubber or wooden hammer to disengage the upper receiver from the lower receiver. DISASSEMBLY OF THE BOLT Lift the recoil spring assembly UP out of its slot in the bolt assembly. NOTE: no further disassembly of the bolt should be needed for routine cleaning. For further disassembly, push out the firing pin stop. This will allow the firing pin, firing pin spring and the firing pin spring support to drop free. With a pointed object, such as a punch of the proper size, push the extractor plunger rearward until the extractor can be lifted out of the side of the bolt. Slowly release the extractor plunger, allowing the plunger and extractor spring to fall free of the bolt. DISASSEMBLY OF THE MAGAZINE Hold the Ruger M10 magazine assembly upside down, keeping the base of the magazine pointed away from people or objects. Insert a 1/16" drift punch through the hole in the base and depress the magazine base plunger approximately .¬.". Slide the base forward very slowly, being very careful to keep the plunger and mainspring under control at all times. If not contained, these parts will fly out with considerable force. With the base fully removed, slowly relax the pressure on the plunger and spring and remove them. Hold the magazine flat with the magazine follower button up. Align the magazine follower button with the circular opening near the lower end of the magazine tube. Lift out the button. The magazine follower can now be removed. CLEAN THE PISTOL Gather together the proper sized cleaning rod with a .22 caliber brass or bronze bristle bore brush and a slotted tip into which a cleaning patch can be inserted. Also needed are clean cloth patches and clean soft cloths. Do not use stainless steel brushes on the weapon unless the Mark II is constructed of stainless steel. Stainless steel brushes will remove the bluing on blued pistols. A bronze or brass "toothbrush" is especially helpful for scrubbing parts. Do not use the bore brush for scrubbing anything except the barrel and magazine housing. Combat Arms and the United States military recommend that you use Break-Free (CLP)(tm). Under no circumstances should you ever use WD-40(tm) on any weapon! If you need a solvent, Combat Arms recommends that you use Shooter's Choice(tm) followed by CLP. The Ruger Mark II should be cleaned at least every 400 rounds and after each firing period. Using a cleaning rod with a slotted tip, run a CLP wetted patch through the full length of the barrel from the chamber end several times to remove loose material. Then attach a bronze or brass bristle bore brush to the cleaning rod and wet it in CLP. Run the bore brush back and forth through the full length of the barrel at least a dozen times. Make sure that the rod is pushed all the way through the barrel until the entire bore brush clears the muzzle end. Do not reverse the direction of the brush until it has completely exited from the muzzle end of the barrel or the bore brush may bind up inside the barrel. Using the toothbrush soaked in CLP, scrub the area around the chamber until it is clean. Remove the bore brush from the cleaning rod and attach the slotted tip again. Run several dry patches through the barrel until they come out clean. If necessary, attach the bore brush to the cleaning rod again and scrub the barrel with a CLP soaked bore brush. Continue the process until the barrel is clean. Failing to do this consistently and properly will cause fouling of the barrel with a natural loss of accuracy. Grease accumulation in the chamber area can interfere with the proper feeding of cartridges from the magazine. Using a loose clean patch soaked with CLP, remove all powder residue from all components of the mechanism. If grease or dirt cannot be removed by merely wiping with the patch, then use your brass toothbrush soaked with CLP. After using the brass toothbrush, wipe all of the scrubbed areas with a clean CLP wetted patch. After cleaning the bore, run a clean dry patch through the barrel and then follow it with a patch that has a light coat of CLP on it. This will put a light coat of CLP on the inside of the barrel and protect it from corrosion. Wipe all surfaces with a clean cloth that has a light coat of CLP on it. If the lower receiver and its mechanism is especially dirty, flood it with CLP, leave it sit soaking for 2 hours and then flush it out with more CLP. Remove the grip panels before soaking or flushing the pistol and make certain that all foreign matter is removed after cleaning. Lightly lubricate the lower receiver with CLP after cleaning. When cleaning the bolt face, breech areas, etc. with the toothbrush, work carefully so as not to damage components. Reassemble the pistol as detailed later in this manual. If the Ruger Mark II pistol is to be stored for an extended period, the final wiping should be done with a heavier coat of CLP. Clean the internal and external parts of the disassembled magazine with CLP. The inside of the magazine can be scrubbed with a bore brush soaked in CLP. After scrubbing, remove all loose material with several clean patches, just like you did with the cleaning of the barrel. Leave a very light coat of CLP on the inside of the magazine and on the magazine spring. - MAGAZINE CLEANING CAUTION - Be careful not to scratch the interior and exterior of the Ruger M10 magazine, particularly along the front section where the bullet tips ride. Be very careful not to bend the magazine lips. Only a very small amount of CLP is needed to provide adequate lubrication of all moving parts in the Ruger Mark II and to prevent rust. Accumulation of CLP can attract particles of dust and dirt which can interfere with the safe and reliable function of the pistol. Do not, therefore, apply excess CLP unless storing the weapon for an extended period of time. If storing the weapon and using a heavy coating of CLP, the weapon should be disassembled and re-cleaned and lubricated with a light coating of CLP before firing. - STORAGE WARNING - If the pistol has been stored, before firing it again, completely disassemble it as detailed elsewhere in this manual, remove all grease and lubricant, apply a light coating of CLP to all parts as described in the section on cleaning and be sure to run a dry patch through the barrel after cleaning with a bore brush soaked in CLP. Do not keep the pistol stored in a leather holster or leather case. Leather attracts moisture, even though the holster or case may appear to be perfectly dry. Never store the Mark II pistol in such a manner as it may be dislodged. Always store the Mark II securely and unloaded. - LUBRICATION WARNING - Firing the pistol with oil, grease or any other material even partially obstructing the barrel may result in damage to the pistol and death or injury to the user and those persons nearby. Never spray or apply any lubricants directly to the ammunition. If the powder charge of a cartridge is affected by the lubricant, it is possible that the charge will not ignite but the energy from the primer in the cartridge case may be sufficient to push the bullet into the barrel where it may be lodged. Firing a subsequent bullet into the obstructed barrel may damage the pistol and cause death or injury to the user and persons nearby. Use all lubricants properly and according to the lubricant manufacturer's suggestions and recommendations. Reassembling the Ruger Mark II ASSEMBLY OF THE MAGAZINE Assemble the magazine in the reverse order of its disassembly, being especially careful to contain the spring and plunger as the base is being locked into place. After assembly of the magazine, test the follower to ensure that it has free movement. ASSEMBLY OF THE BOLT The bolt is assembled in the reverse order of its disassembly. When installing the firing pin spring, make certain that the front of the support curves DOWN into the bolt. After assembly, test the extractor and firing pin for free movement. Put the recoil spring assembly back into the bolt. INSTALLATION OF THE UPPER RECEIVER ASSEMBLY Grasp the lower receiver in a natural shooting position. Point the pistol upward vertically and pull the trigger to pivot the hammer backward to a cocked position. Lower the pistol to a horizontal position. Place the upper receiver about ¬" ahead of its final position and press it backward and downward so that the trigger guard lug engages the front recess on the bottom of the upper receiver. The upper receiver is properly aligned when the rear end of the upper receiver is approximately even with the rear end of the lower receiver. If proper alignment is not achieved by mere hand pressure then it is necessary to strike the muzzle with a plastic, rubber or wooden hammer. Inspect the inside of the receiver to see if the hammer is up. If the hammer is up, the bolt will not go into the receiver. If the hammer is up, point the pistol up vertically and pull the trigger to make the hammer go to the cocked position and ensure that the hammer strut is free. INSTALLATION OF THE BOLT ASSEMBLY INTO THE RECEIVER With the muzzle still pointing slightly upward, insert the bolt into the receiver SPRING SIDE UP. If you put it straight in, the bolt will easily slide right into the receiver. - FIRING PIN STOP WARNING - When sliding the bolt assembly into the receiver, be certain that the firing pin stop is in the bolt. If the bolt is assembled without the firing pin stop in place, the first time the Mark II pistol is dry fired (no live cartridge in the chamber), the firing pin will be free to move forward to the extent that it will dent the rear face of the chamber, thus rendering the upper receiver useless and beyond repair. INSTALLATION OF THE MAINSPRING HOUSING ASSEMBLY Point the empty pistol downward and pull the trigger until the hammer falls forward to its vertical (fired) position. Grasp the mainspring housing and insert the mainspring housing into the receiver by positioning the mainspring housing pin into the bottom of the hole in the lower receiver and push it straight up through the hole in the upper receiver. As the mainspring housing pin is pushed upward through the receivers, it passes through the slot in the bolt and also passes by the rear end of the recoil spring guide, camming the recoil spring guide forward to put initial tension into the recoil spring. Continue pressing the mainspring housing pin upward through the receivers until the mainspring housing pin protrudes about 1/8 inch above the top of the upper receiver. During this step, be certain that the rear of the bolt is flush with the rear of the receiver and that the hammer is in its fired (forward) position. When the hammer is in the forward position, it is then possible to observe the hammer strut. The mainspring housing pin will snap into place when it has traveled to its correct position. VERIFY THAT THE HAMMER IS AGAIN FORWARD Point the empty pistol down towards the floor and pull the trigger. This will cause the hammer to fall forward. Release the trigger and do not touch it again! REPOSITION THE HAMMER STRUT Point the MARK II straight up until you hear the hammer strut fall back with a slight click. You will have to raise the pistol rapidly to cause the hammer strut to fall back. Do not pull the trigger. Keep the Mark II pointing upward. LATCHING THE MAINSPRING HOUSING The mainspring housing is now ready to be swung shut but it is essential that the hammer strut comes to rest on the mainspring plunger as the housing is closed. The mainspring plunger lies inside the mainspring housing and may be seen through the slot in the upper end of the housing. If the hammer strut does not contact the mainspring plunger as the housing is swung shut, it will either be impossible to complete the closure of the housing or the housing may be closed but it will be impossible to draw the bolt all the way back. It is also essential that the hammer itself be in its uncocked forward position (resting against the firing pin) as the mainspring housing is swung shut. With the MARK II still pointing up vertically and tilted at a slight angle to cause the hammer strut to drop into the correct position to meet the mainspring plunger in the mainspring housing, close and latch the mainspring housing by pushing the latch into its original position with the heel of your hand. TESTING FOR PROPER ENGAGEMENT When proper engagement is achieved, closure is complete against the tension of the mainspring, which can be felt as the mainspring housing is pushed into the recess in the back strap. To find out if you did everything correctly, grasp the bolt ears and pull the bolt back. If the bolt comes all the way back, you reassembled the Ruger Mark II correctly. If the bolt fails to come back, it is because the hammer strut is improperly positioned. If the hammer strut is improperly positioned, then open the mainspring housing again and go back to the step entitled VERIFY THAT THE HAMMER IS AGAIN FORWARD. - USE OF FORCE CAUTION - It isn't the amount of force that does the job but how that force is applied. If all else fails, bring the pistol into Combat Arms and we'll show you how to do it at no charge if you purchased the Mark II here. Otherwise there is a $5.00 fee. Everyone agrees that the Ruger factory manual for the Mark II pistol leaves a lot to be desired. Sorry, but the only thing that will change that is if you, the consumer, write to Sturm, Ruger & Company, Inc. and complain. Combat Arms has spare factory manuals if you need one ($1.00). - RECALL NOTICE - If your serial number is 210-92816 to 210-94772 or 211-28500 to 211-40000, Sturm, Ruger & Co. Inc. advises that two (2) pistols in the aforementioned serial number range have been discovered to fire if the trigger is pulled when the safety is on S and then the safety is moved to the F position. If, with an empty pistol, you cock the pistol, put the safety to S and pull the trigger and then put the safety to F and pull the trigger, you should hear a click as the hammer falls in a properly functioning pistol. If you do NOT hear the click, the pistol can fire simply by moving the safety to the F position. Do not use the pistol if it does this! Ship it at once via UPS to Sturm, Ruger & Co. Inc., Dept. MKII, Lacey Place, Southport, CT 06490. If you prefer, Combat Arms can insure and ship the weapon for you for $10.00. Ruger will repair the pistol without charge to you. . - About the Author - Born in Indianapolis, Indiana on March 6, 1945, Richard M. Bash (known to his friends as Dick) graduated from Purdue University and did graduate work at the University of Southern California. For approximately 10 years Dick flew as a flight engineer aboard Boeing 707, Boeing 727 and Lockheed C-130 aircraft. After having traveled to 108 different countries, Dick settled in the San Francisco Bay area where he opened Combat Arms in 1983. He lives with his wife, Flora, in Hayward, California and enjoys shooting, computers, ham radio (KL7IHP) and reading. He is a Heckler & Koch factory trained armorer and a graduate of the Law Enforcement Armorer School at Lassen College in Susanville, California. A perennial student, he presently taking courses at Chabot College in Hayward. Dick wrote this manual because so many users had questions about the proper way to disassemble, clean and assemble the Ruger Mark II and there was a severe lack of information available. Written suggestions for improvement of this manual are also welcomed. . - Acknowledgment of Trademarks - Combat Arms wishes to acknowledge the trademarks of the following products along with their respective companies. Mark I, Mark II, Ruger Sturm, Ruger & Co. Inc. Break-Free, CLP San-Bar Corp. WD-40 WD-40 Company Shooter's Choice Venco Industries Inc. .