Bolt Action Rifles. Wayne Zwoll

the action, grasp the bolt handle and push the bolt forward. As the bolt moves forward it pushes the top cartridge in the magazine into the chamber. The cartridge head slides under the extractor hook on the final forward movement of the bolt.

      An underside view of the M98 Mauser bolt shows the dual-opposed locking lugs (A), extractor (B), extractor collar (C), dual oblong vent holes (D), and safety lug (E). This 98a carbine bolt has a bent down handle with the under- side of the grasping ball flattened and checkered.

      During the final forward movement of the bolt, and on rotating the bolt clockwise to the locked position, the sear engages the cocking piece to hold it back as the locking lugs pull the bolt fully forward to lock and seat the cartridge in the chamber. The rifle can now be fired by pulling the trigger, releasing the firing pin under mainspring tension, or the action can be made “safe” by swinging the safety to the right. Cartridges can be extracted and ejected safely by swinging the safety to its intermediate or upright position and opening and closing the bolt.

      The firing pin can be lowered without snapping it by merely swinging the safety to the left, or fire position, raising the bolt handle, and then holding the trigger back as the bolt is rotated down to its locked position. This should only be done with an empty chamber.

      Takedown and Assembly

      Check the chamber and magazine to be certain the rifle is unloaded. Close the bolt and place the safety in the upright position. Now raise the bolt handle, swing the bolt-stop to the left, and draw the bolt from the receiver.

      To disassemble the bolt, proceed as follows: Depress the bolt sleeve lock plunger, then unscrew the bolt sleeve and firing mechanism from the bolt; place the firing pin tip on a hard surface and, firmly grasping the bolt sleeve, press the bolt sleeve down; turn the cocking piece one-quarter turn in either direction, and lift it off the firing pin. Firing pin and mainspring can now be separated. Swing the safety to the right and pull it out of the bolt sleeve. Depress the bolt sleeve lock plunger and rotate it counterclockwise until it is released; pull it and the spring from the bolt sleeve. Remove the extractor by lifting the front (hook end) away from the bolt so that it can be turned to the bottom of the bolt; the extractor can now be removed by pushing it forward. Reassemble in reverse order.

      To remove the bolt-stop, turn the bolt-stop screw out, and lift it from the receiver. Pull the ejector forward out of the bolt-stop. Place the bolt-stop in a vise and, using a drift punch, drive the spring forward until its end slips down. Now insert a small screwdriver between the end of the spring and bolt sleeve, and pry the spring forward. In reassembling the spring into the bolt-stop, the end of the spring must be raised over the edge of the bolt-stop when it is being driven into place.

      To remove the barrel and action from the military stock, first remove the upper and lower barrel bands from the forend, then remove the two guard screws from the bottom of the trigger guard. The barrel, action, and magazine can now be lifted out of the stock.

      Remove the floorplate by depressing the floorplate plunger with a pointed tool (or pointed bullet tip) put through the hole in the rear of the plate, then slide the plate to the rear. The magazine follower and its spring will come out with the plate. The three parts can be separated by sliding the plate and follower off the ends of the spring. Remove the floorplate plunger by driving out the crosspin from the rear of the magazine box. Remove the trigger and sear by driving out the trigger and sear pins. Reassemble in reverse order.

      Model 98 Mauser action open.

      Large and Small Ring Actions

      Model 98 actions with a receiver ring about 1.410” in diameter are commonly called “large ring” Mausers. Most M98 sporting and military rifles made up to the end of WWII are based on this large ring action. Most of the commercial M98-type actions made after WWII, like the FN, are also of the large ring type.

      The “small ring” Mauser actions have a receiver ring diameter of about 1.300”. A lot of the early M98 carbines, like the 98a, were based on the small ring action. The most notable later carbine using this action was the lightweight Czech Model 3¾0.

      The difference between the large and small ring actions is readily discernible by sight or touch, and there is no need to use a caliber to identify them. On the small ring action the left side of the receiver is straight, including part of the bridge, the wall and ring. However, on the large ring action this surface has a notable jump where the receiver wall merges with the ring, which can be seen and felt.

      Because the large ring action has a thicker wall of metal surrounding the sides and top of the barrel shank and locking lug recess areas, it naturally is stronger than the small ring action. Just how much stronger is difficult to say. However, German gunmakers considered the small ring action strong enough for the most powerful 8mm military or sporting cartridge. Generally, the large ring actions are preferred and recommended for use with belted magnum and larger rimless cartridges like the 30-06 and 8mm. The small ring actions are preferred for lightweight sporters using small rimless cartridges like the 7mm and 6mms.

      Steel and Heat-Treatment

      In our study of Mauser actions preceding the M98, we noted that Paul Mauser made each successive action better, stronger and safer than the preceding model through better design. It is generally agreed by experts that the M98 Mauser obtains its strength from its design rather than by the use of specially formulated or alloyed steels, or by some special heat-treatment. It is not known just exactly what kind of steels were used to make the various parts, or the details of the heat-treatments, but there is no doubt that whatever steels and heat-treatments were used, they were entirely adequate to make the M98 the world’s most successful military turnbolt action.

      It is believed that the M98 receivers were made of tough quality low-carbon steel. After machining, the only heat-treatment the receiver got was carburizing (case-hardening). This resulted in a hard outside surface to resist wear and rust, but left the core relatively soft for strength.

      Receivers of the pre-WWI era, especially the small ring type, tend to be somewhat softer then these manufactured in the 1920s, ’30s and early ’40s. I have observed that receivers made late in the WWII period, or those dated “44” and “45,” are sometimes either very soft or hard, mostly the latter. The normal range of hardness for a good receiver seems to be about 35C Rockwell.

      Model 98 bolts and some of the other working parts of the action were evidently made of medium- or high-carbon steel, so that these parts could be made much harder.

      There seems to be no evidence to indicate that any re-heat-treatment of a soft M98 receiver will improve it or make it stronger. It is inadvisable, therefore, to have this done.

      This brings up a question I’m often asked: “How do I go about selecting a good original Mauser 98 military action on which to build my own custom rifle?”

      My suggestions are: Buy the action, or a complete rifle from which the action is to be taken, from a reputable dealer who will refund your money if for any reason you are not satisfied with the action or rifle they sell. Avoid those dated before 1920 and those dated after 1943. Finally, if possible to do so, pick one that was made by one of the better plants. For example, you can hardly go wrong in picking an action made in the 1930s having such names (or code letters) as Mauser, DWM, FN or Brno (VZ-24) stamped on the receiver. After getting one of these actions there is no point in having the receiver tested for hardness; whether it is somewhat harder than 35C Rockwell, or considerably softer, the action is still good.

      One final word of caution about very soft receivers: If you have an M98 rifle and you want to use the action for building a rifle—if of pre-1920 manufacture, or if the rifle shows evidence of having been used a great deal—it would be a very good idea to testfire it, preferably with several full-service rounds. After each firing, if the bolt handle can only be raised with difficulty, this may indicate locking lug set-back in the receiver ring. This is usually a sign that the receiver is very soft, and that