Gun Digest Book Of Rimfire Rifles Assembly/Disassembly

Beretta ARX-160

Beretta has a new full sized assault rifle called the ARX-100 in service with their military. As with many such rifles, there is a rimfire replica imported into the U.S. that otherwise looks and feels like the original. The ARX-160, made by Walther, does not have the ambi switching features of the centerfire rifle, but just about everything else is there.

Disassembly:

1. With the stock folded, rotate the safety up past the safe position. You will feel the tension. At this time, depress the bolt backstop plate inside the rear of the receiver. When the plate is fully depressed, pull the pistol grip down and off the receiver.

2. Pull the bolt assembly all the way to the rear of its motion and pull the operating handle out to the side. Then the bolt assembly can be fully removed out the back of the receiver.

3. Loosen these two screws in the slots to release the barrel.

4. The pseudo gas block can be removed by punching out his roll pin. A similar but smaller pin holds on the flash hider. Remove the pin and unscrew the flash hider.

5. The stock, if necessary, can be removed by punching out the hinge pin(s). This catch should be depressed to remove the stock latch and spring (picture A). The buttplate can be removed by manually pulling down on the long adjustment latch and pulling the plate out to the rear (picture B). The latch and spring can be removed by driving out the pin in the middle of the sides of the buttplate.

6. The rails are retained by spring pins. The receiver halves are held together by several screws which are concealed by the top and bottom rails (picture A), and the Beretta and ARX-160 panels on the left side. The panels are snapped in place; the snap tabs can be displaced with a small screwdriver by reaching up inside the receiver from the bottom (picture B). Further disassembly should not be required unless the bolt catch (just below the left ejection port) is broken.

7. Tap out this pin to separate the bolt pieces.

8. The extractor spring and plunger can be removed by inserting a small tool in order to lift the spring out of its slot. The extractor can be removed once the spring and plunger are gone.

9. Lift the rear of the firing pin up slowly to remove it and its underlying return spring.

10. Should it be necessary to disassemble the recoil spring assembly, it can be done by unscrewing the guide rod from its nut. The nut is positioned on the backside of the buffer/takedown section at the rear of the assembly.

11. This small spring in the underside of the bolt carrier is a detent for the pin that was punched out in step 7. Leave it there and try not to break it.

12. Fully depress the right side magazine catch button to expose the left button. Pull the left button to the rear and off the assembly (picture A). The remaining assembly can be broken down by removing this screw (picture B).

13. Remove the bolt inside the pistol grip. Then lift the trigger housing assembly out of the pistol grip.

14. Pull the safety levers out to either side.

15. Remove the six screws on the left side of the trigger housing (picture A). Note that the bottom three are shorter than the top three. Remove the left side of the housing (picture B). This is the orientation of the internals.

16. Remove the trigger and sear assembly.

17. Remove the safety. Do not lose its spring and plunger, inserted in the left side of the safety.

18. This large plunger is the device that holds the bolt assembly and pistol grip in place in the receiver. Remove it next, taking care to control the assembly, as well as the hammer assembly springs, as both continue to be under tension.

19. This is the hammer spring seat. Tease it out and control the spring, then remove the hammer. The hammer and strut are connected with a pivot pin that should ordinarily stay in place.

20. The trigger/sear assembly can be broken down by removing the two large pins. The disconnector is a small Y shaped piece on the right side that is held in place by a coil spring wrapped around the rearmost pin. Don’t lose this spring, should the need arise to break this assembly down.

21. This screw holds a spring that tensions the takedown extension movement of the safety. Remove if necessary.

22. The front and rear sight assemblies are both retained by large roll pins. Punching out these pins will allow the sights to slide off the receiver to the front and rear respectively. Further disassembly of the sight assemblies is not recommended.

Reassembly Tips:

1. When replacing the left trigger housing wall, make sure the spring that is screwed into the left wall, shown at the right in this picture, enters the safety at this location, shown on the left.

2. The disconnector and sear arm must be arranged in this fashion when reinstalling. Failure to do so will immobilize the trigger.

BRNO Model ZKM 452

Similar/Identical Pattern Guns

The same basic assembly/disassembly steps for the BRNO Model ZKM 452 also apply to the following gun:

BRNO Model ZKM 452D

The ZKM-452 was introduced in 1992, and this high-quality rifle was imported from Czechoslovakia by Action Arms. There was also a Deluxe version, which differs only in stock quality and added checkering. A synthetic stock is also offered as a lower-priced option. The present importer of the rifle is CZ-USA.

Disassembly:

1. Remove the magazine. Hold the trigger to the rear, open the bolt, and remove the bolt toward the rear.

2. Remove the front stock mounting bolt.

3. Remove the rear stock mounting bolt, located between the trigger guard and magazine well.

4. Remove the action from the stock.

5. The stock buttplate and the trigger guard unit are retained on the stock by two wood screws.

6. Push out the trigger pin toward either side. Restrain the trigger, as the spring is under tension.

7. Ease the trigger downward. It is not taken off at this time, as it is still retained by its sear-contact cross pin. That cross pin, and the one that pivots and retains the spring guide, are riveted in place, and routine removal is not advisable. The trigger spring and the adjustment lock-washer can be removed from the guide at this point. Take care that the small washer isn’t lost.

8. Restrain the sear, and push out the sear cross pin. Caution: The sear spring is powerful, and there is a small ball bearing between the spring and the receiver. Control it and ease it out. Considering the reassembly difficulty, this system is probably best left in place unless removal is necessary for repair or refinishing.

9. Remove the sear and trigger assembly downward. After removal, the parts are easily separated.

10. The magazine catch and its spring are pivoted and retained by a cross pin. Caution: Control the catch and its spring as the pin is drifted out. The magazine housing is retained on the receiver by two screws, at front and rear.

11. The front sight hood can be sprung outward slightly and slid forward out of its tracks. Backing out the front sight elevation adjustment screw will allow the sight blade to be slid down and forward for removal.

12. The rear sight is retained Mauser-style. Push down at the front and slide it toward the rear for removal. There is no cross pin.

13. To remove the twin extractors, insert a tool and pry the end of the saddle-spring outward, just enough to clear its retaining shelf. As the spring is removed, control it. The extractors are then lifted out of their recesses.

14. With the bolt held securely, use a tool to push the combined striker and firing pin toward the rear, and turn the bolt handle, allowing the striker to move forward to fired position.

15. Grip the front part of the bolt in a padded vise, and use a tool to depress the safety retainer until the safety can be lifted out. Caution: Control the retainer.

16. Easing the spring tension, remove the safety and the retaining plunger.

17. Remove the striker assembly toward the rear. The spring is easily removed from inside the striker.

18. Remove the bolt handle toward the rear.

Reassembly Tips:

1. When replacing the sear and trigger assembly, temporarily install the rear stock-mounting bolt in order to supply a compression surface for the sear ball bearing and spring, as shown. Remember to hook the forward trigger cross pin over the sear. Temporarily insert the bolt body to stop the sear inside the receiver. When the ball and spring are compressed, insert a small drift to hold the sear for insertion of the sear cross pin. This is a difficult operation. Keep a shop cloth or apron around the receiver to arrest the ball if it slips.

2. Be sure the trigger spring adjustment washer is installed in the proper orientation, with the locking dimples downward toward the adjustment nut, as shown. Remember that the upper end of the guide must enter its hole in the receiver before the trigger cross pin is reinserted.

3. When replacing the striker assembly in the bolt, remember that the angled lug goes at the bottom to contact the like surface on the bolt handle, as shown.

4. When the safety and its retaining plunger are installed, it will be necessary to again use a padded vise to hold the front of the bolt. Be sure the plunger is oriented as shown, and that the safety is straight across as it is inserted.

5. Before the bolt can be reinserted in the receiver, the striker must be re-cocked. Hold the front part of the bolt firmly, and turn the handle until the locking lug is at the bottom, as shown.

Browning A-Bolt 22

Similar/Identical Pattern Guns

The same basic assembly/disassembly steps for the Browning A-Bolt 22 also apply to the following gun:

Browning A-Bolt 22 Gold Medallion

The Browning A-Bolt in 22 LR and 22 WMR was also offered in a Gold Medallion version that differs only in fancy stock wood and other embellishments. The standard rifle was introduced in 1986, but fewer than 150 were made in that year. The deluxe model was first made in 1988, and the 22 WMR version in 1989. Among the high-class 22 bolt actions, the A-Bolt ranks as one of the best. The A-Bolt 22 was discontinued in 1996.

Disassembly:

1. Remove the magazine, open the bolt, and depress the bolt latch. Remove the bolt toward the rear.

2. Remove the stock mounting bolt, located just forward of the magazine well.

3. Remove the rear stock mounting bolt, located at the rear of the trigger guard unit.

4. Remove the trigger guard assembly downward. The magazine catch and its spring, located in the guard forward of the trigger, are best left in place in normal takedown. If removal is necessary for repair, insert a drift or rod through the loop at the rear of the catch, and draw it back until its side wings align with the exit cuts; then lift it out. Control the spring.

5. Remove the action from the stock, upward.

6. Drift out the roll pin at the front of the trigger housing.

7. Use an 8mm socket to remove the mounting bolt at the rear of the trigger housing. Take care that the lock washer is not lost.

8. Remove the trigger housing downward.

9. The bolt latch can be removed from the left side of the receiver by backing out its retaining and pivot screw. Restrain the latch as the screw is taken out, and ease it off. Remove the spring. In the front of the latch, a vertical roll pin retains the bolt stop/guide pin.

10. Because several of the parts in the trigger group are set or staked at the factory, disassembly of this system should be reserved for repair purposes. The sear pivot, for example, is riveted on both sides, and it is not routinely removable.

11. If necessary, the safety system can be removed. First, pry off the C-clip on the left side of the housing. Control it during removal, as it will snap off when freed.

12. Control the torsion spring, and remove the safety toward the right.

13. Remove the safety spring.

14. Move the connecting rod and the safety button out toward the rear.

15. The connecting rod is staked on the left side of the button, and these parts are not routinely separated.

16. Unhook the safety-lever spring at the rear to release its tension.

17. Insert a drift in the access hole on the right side, and drift out the safety-lever post toward the left. Remove the lever and spring.

18. In order to remove the safety bolt lock pin, it is necessary to grip its side roll pin with pliers and pull it out. The lock pin is then taken out upward. Damage to the roll pin is likely, so this should not be done in normal takedown.

19. While the sear is not routinely removed, its spring is accessible by removal of the sear limit screw. However, this screw is factory set for proper engagement of the sear contact stud in the top of the trigger. If the screw is disturbed, it must be reset.

20. If the trigger has to be removed for repair, the first step is to unscrew and take out the safety post, shown here.

21. After the safety post is removed, drift out the trigger pin and take out the trigger and its spring downward. The sear contact stud in the top of the trigger is a separate part. In normal takedown, this system is best left undisturbed.

22. To remove the extractor, insert a small tool to depress the plunger and spring toward the rear, and lift out the extractor. Caution: Keep the plunger and spring under control and ease them out.

23. The combination ejector and firing pin can be removed by drifting out this roll pin, but the plunger and spring may be difficult to remove without further disassembly of the bolt. It can be done, though, if only this part needs to be replaced in repair. The forward roll pin is a guide only, and it does not have to be removed.

24. Hold the bolt firmly at the front, and turn the handle to lower the striker to fired position, as shown.

25. Restrain the bolt end piece and use an Allen wrench to remove the bolt sleeve retaining screw. Caution: Even in fired mode, the striker spring has some compression, so control the end piece.

26. Remove the end piece and striker assembly toward the rear.

27. Remove the bolt handle toward the front.

28. With the front of the striker against a firm surface, such as a workbench edge, tip the striker and spring assembly downward, out of the bolt end piece.

29. The striker, its spring, and the collar at the rear can be separated from the cocking piece by drifting out the roll cross pin. Caution: The captive spring is still under tension. Except for repair, this system should be left intact.

30. The cartridge guide is a separate part, driven into a well in the underside of the receiver. If it is damaged and must be replaced, it can be driven out downward. Replacement requires precise positioning. In normal takedown, even for refinishing, it is best left in place.

Reassembly Tips:

1. When installing the striker assembly in the bolt end piece, place the spring collar against the shoulders in the end piece, and push the assembly back and inward to snap it into place.

2. When replacing the Allen screw, be sure the screw hole is precisely aligned before turning the screw into place.

3. Before the bolt can be put back into the receiver, the striker must be in cocked position. Grip the front of the bolt firmly in a shop cloth or a padded vise, and turn the handle until the lug is in the position shown.

4. When installing the safety-lever, be sure its front fork engages the bolt lock side pin, as shown. After the post is drifted into place, remember to rehook the spring under the lever at the rear.

Browning Model BL-22

Similar/Identical Pattern Guns

The same basic assembly/disassembly steps for the Browning BL-22 also apply to the following gun:

Browning BL-22 Grade II

Browning’s neat little lever-action 22 has been made by Miroku of Tokyo for many years, and it will probably be around for many years to come. It is unique among currently-made 22-caliber lever actions in having the trigger mounted in the lever, rather than in the receiver. It also has a very short lever arc that allows operation of the action without removing the hand from the wrist of the stock. For the nonprofessional, some elements of the takedown and reassembly can be rather difficult. Note that in 2005 the same rifle was offered in 17 Mach 2 chambering as the BL-17.

Disassembly:

1. Remove the inner magazine tube, and set the hammer on its safety step. Partially open the action. Take out the large cross-screw at the rear ofthe receiver.

2. Move the sub-frame and buttstock assembly straight out toward the rear. Move it slowly, and insert a fingertip through the ejection port to restrain the ejector, as it will be released as the front of the bolt clears it.

3. Remove the ejector spring from its recess in the left inner wall of the receiver. Move the ejector downward off its fixed pivot post, and take it out.

4. Tip the bolt upward at the rear, and move it a short distance toward the front.

5. Bring the rear of the bolt back down parallel with the top of the sub-frame, then lift the bolt off upward.

6. The firing pin and its return spring are retained in the bolt by a roll cross pin. Drift out the pin, and remove the firing pin and spring toward the rear.

7. The bolt cover plate on the right side is taken off by prying it gently outward at the rear, equally at the top and bottom, until it snaps off its fixedmounting pin.

8. Insert a screwdriver blade between the extractor and its plunger, depress the plunger, and remove the extractor from its recess in the bolt. Caution: Take care that the screwdriver doesn’t slip, and ease out the plunger and spring.

9. Depress the carrier, and remove the locking block from the lever link toward the left.

10. Unhook the carrier spring and allow its front arm to swing upward, relieving its tension.

11. Drift out the carrier pivot pin toward the right, and remove the carrier and its spring upward.

12. Removal of the carrier pin will also release the hammer stop block, and it can now be removed upward.

13. Restrain the hammer, pull the trigger, and ease the hammer down beyond its normal forward position, relieving the tension of its spring. Drift out the hammer pivot pin toward the right, and remove the hammer and its attached spring guide upward. The guide pin is staked in place, and should not be removed in normal takedown.

14. Open the lever, and remove the mainspring and its lower guide downward.

15. Drift out the lever link pivot pin.

16. Removal of the pin will allow the lever to be pivoted downward beyond its normal position, and the link can then be removed toward the right.

17. Drift out the lever pivot pin, and remove the lever downward.

18. Drift out the roll cross pin at the rear of the trigger, restrain the sear link, and remove the link and its spring upward.

19. Drift out the trigger cross pin and remove the trigger and its spring upward.

20. Remove the buttplate, and use a B-Square stock tool or a long screwdriver to remove the stock bolt. Take off the stock toward the rear.

21. Push out the cross pin that retains the sear, and remove the sear and its spring downward.

22. Remove the cross-screw in the front barrel band.

23. Drift out the cross pin in the rear barrel band, and slide the band off the forend toward the front. Remove the outer magazine tube toward the front, and take off the forend downward. The front barrel band can be removed only after the front sight is drifted out of its dovetail.

Reassembly Tips:

1. After the sear is installed, flip it over and insert the spring, then rotate it back into position, and insert a tool from the top to nudge the spring onto its plate inside the frame.

2. After the hammer is installed, tip its spring guide upward, and fit the spring and lower guide onto it.

3. Swing the mainspring assembly downward, with the lever in closed position. Pull the trigger to release the hammer, and tip it forward beyond its normal lowered position. Snap the nose of the lower spring guide into its recess on the lever. Open the lever, and insert a fingertip to support the underside of the spring while slowly cocking the hammer. Caution: If solid resistance is felt, stop and be sure that the spring is being kept straight (it will tend to bow downward).

4. When replacing the locking block on the lever link, note that its side projection must be at the right rear, as shown.

5. Grip the ejector spring with forceps or sharp-nosed pliers for insertion. The same procedure can be used for the ejector. When the spring and ejector are in place, insert a fingertip through the ejection port to hold them while sliding the bolt and sub-frame back in.

6.When replacing the carrier and lever link, be sure the pointed front arm of the lever link lies on top of the carrier guide pin.

Browning Semi-Auto 22

Similar/Identical Pattern Guns

The same basic assembly/disassembly steps for the Browning Semi-Auto 22 also apply to the following guns:

Browning Standard Auto Grade II

Browning Standard Auto Grade III

Browning Standard Auto Grade VI

Norinco 22 ATD

Remington Model 24

Remington Model 241

This neat little semi-auto rifle was first produced in 1914 by FN in Belgium. In 1922, production rights for the U.S. were leased to the Remington company, and it was made by them as the Model 24 and Model 241 until 1951. In 1956, a slightly altered version was introduced by Browning, and it was made for them at FN until 1974. From that time to the present, the gun has been made for Browning by Miroku of Japan. Through all of this time, the internal mechanism has been essentially unchanged. There are some minor differences in the extractor and cartridge guide systems, but the instructions will still apply.

Disassembly: