Chapter Eight Assembling and Testing

When all the component parts are finished and semi-polished, the pistol is ready to be assembled and test fired. This step is done before the components are finally heat treated, polished, and blued, because you will likely have to make adjustments on some of the parts before the pistol will function as designed. Prior testing at this point will save the trouble of refinishing and rebluing any parts marred, modified, or scratched during the test.

Be sure that all working parts have a smooth finish, free from burns and scratches. Flat parts, such as the sear and trigger must have flat smooth sides, square with the top and bottom, and finished until they feel slick when handled.

A good trick to finish these sides is mentioned in Volume One of this series in Chapter Ten. Begin it by placing a sheet of abrasive cloth on top of a piece of plate glass, then firmly rub the part to be polished back and forth across the mounted abrasive cloth. An extremely fine finish is obtainable from this process, though it is laborious and time consuming.

Once the interior components are finished to your satisfaction, begin assembling the handgun by placing the appropriate coil spring in position between the sear and frame; pin the sear in place. Pin the trigger in place in the frame, then fit the trigger bar-disconnector, pin, and spring in their respective locations.

Insert the hammer into position, then push the hammer pivot pin into place. Position the hammer strut and hammer spring in their places, with the protruding end of the hammer strut fitting into the notch in the hammer's lower rear side. The hammer strut's lower end fits into the slot in the upper end of the magazine retainer. Push the magazine retainer upward against the pressure of the hammer spring, until the pivot pin in the magazine retainer slips into the slots at the frame's lower rear end. Since these frame slots angle downward and forward, pressure

exerted downwards by the hammer spring holds the magazine retainer in place, which in turn retains the magazine in position. Pushing the magazine retainer to the rear releases the magazine, permitting it to be removed from the gun.

Next, insert the safety and takedown levers into their holes in the frame from the left side, and fit them with their retainer pins on the right side. The ejector is positioned in its frame slot at the left rear edge of the magazine opening, and pinned in place.

At this point, check the action carefully for roughness and binding by cocking the hammer and pulling the trigger. Hold the hammer back slightly with your thumb while doing this to prevent it from slamming forward, which may cause the hammer pivot pin to break. Watch the sear as the hammer is cocked. Does it snap cleanly and crisply into the hammer notch? Or does it drag or flop weakly into the notch when the hammer is fully cocked? If it does the latter, then either the retainer pin is too tight in the hole through the sear and the hole must be reamed slightly, the sear spring is weak and must be replaced, or rough edges on the sear body are binding and must be removed.

Try thé disconnector for freedom of action and proper functioning. Depress the disconnector leg extending upward through the top of the frame, about 1/8 of an inch. This action should push the trigger bar downward, away from the sear, causing the sear to engage the hammer notch. The hammer must hold in the cocked position, regardless of whether or not the trigger is depressed. Releasing the pressure on the disconnector leg must cause the trigger bar to snap upward without any drag or hesitation, allowing the trigger bar's notched rear end to engage the sear, and pull it free from the hammer notch when the trigger is pulled.

The way this works is not really as complicated as it sounds. With the slide fully forward in the battery position, a recess in the breech block allows the upper end of the disconnector leg to ride upward through the frame. This permits the trigger bar to engage the sear, and pull it forward when the trigger is pulled. The hammerthen falls, driving the firing pin forward into the primer of the chambered cartridge, and the gun fires.

Ensuing recoil drives the breech block to the rear, and the ledge directly forward of its recess depresses the disconnector. The trigger bar moves downward, out of engagement with the sear, and the sear engages the hammer notch. It holds the hammer in its full cock position after the rearward motion of the recoiling breech block has pushed it to the rear.

When the breech block reaches the end of its rearward travel, the recoil spring forces it forward again. During this motion, a cartridge is stripped from the magazine and fed into the barrel chamber. As the ledge in the forward-

Turning the takedown lever forward allows the slide assembly to be pushed slightly forward, and removed. Note the cut-away portion of the grip's left side around the sately.

travelling breech block once again permits the disconnector to move upward, the trigger again engages the sear.

Since the notch in the trigger bar moves forward when the trigger is held to the rear, the trigger must be released and allowed to move fully forward again before the notched trigger bar can re-engage the sear. Re-engage-ment in this manner enables the pistol to fire only a single shot each time the trigger is pulled, preventing full automatic fire.

I am sure there are some readers who will be tempted to leave this feature out, but I admonish them not to do so. The idea of a full-automatic pistol appeals only to the ignorant and the uninformed. Remember that not only is a full-automatic pistol highly illegal, it is also inaccurate and dangerous. A lightweight pistol of this design cannot be held on a target accurately when more than one round is fired with each pull of the trigger. Muzzle climb is compounded as each succeeding round is fired automatically, preventing any semblance of precise shot placement. Such a weapon endangers anyone else in the area as well as the shooter himself.

But in spite of my warnings, some of you will convert this pistol to fire on full automatic anyway. If you must do so, at least do it right. By this I mean take extra care in fabricating the entire receiver assembly, so that it is as strong and durable as is possible. Remember that it will be subjected to much greater stress when the pistol fires automatically.

The conversion is actually quite simple to accomplish. Begin by cutting off the disconnector portion from the trigger bar that is shaded in the diagram. The firing pin must also be longer than for the semi-auto design, so that its tip protrudes approximately .060 inch through the boltface when the hammer is down. This is necessary because the hammer falls as the breech block returns to its forward or "battery" position. The shorter, inertia-type firing pin may not be driven forward rapidly enough for reliable ignition of the cartridges when they are fed automatically.

When the pistol's firing mechanism works to your satisfaction, the grips are fixed in place by the single screw extending through the left grip and frame, which screws into the threaded nut or escutcheon in the right hand grip. With the grips in place, try the action and disconnector several more times to make sure that all parts still function as designed without binding. If binding does occur, smear a thin coating of lipstick or inletting black on the edges of any parts that do bind. Mount the grips back in position, and try the action again. Remove the grips, and carefully trim away any of the grips' inner surface marked with the lipstick or black. Repeat until all parts move freely and correctly.

Silver-solder the front and rear sights in their respective positions atop the receiver. Using a pre-manufactured paste-type soldering mixture to affix the sights greatly simplifies this procedure. Coat with paste both the sight base and the section of the receiver it sits upon. Clamp the sight base into position on the receiver, and apply enough heat to it with an acetylene torch to melt the paste mixture. Allow to cool, remove the clamp, and mount the other sight base in the same manner. If silver solder paste is not available, make a similar mixture by filing wire or rod-type silver solder into dust, then mixing the dust with paste-type flux, which is available at most welding supply houses.

That method of applying silver solder is adaptable to any situation where a close-fitting joint with an even distribution of the bonding agent is required.

The receiver is now fitted to the frame. Be sure to carefully file the lugs on the bottom of the receiver until they mate precisely with the corresponding ledges in the frame. The takedown lever should beturnableto its locked position. These joints must mate closely with no play at all. Any loose-fitting parts will quickly batter and wear when the weapon is fired.

Slip the firing pin spring over the body of the firing pin from its front end, and insert this assembly into its hole in the breech block's rear end. Press the firing pin retaining pin into its hole. When the firing pin's base is flush with the bottom of the hammer slot, the firing pin nose must be flush with or slightly below the face of the breech block. If correctly executed, this safety feature allows the pistol to be carried with the hammer down and a round in the chamber. Please note that I do not recommend that the pistol be carried in this manner. But for those who wish to ignore my warning, I say only that it is reasonably safe if the firing pin is fitted exactly as described.

Next, fit the extractor into the slide by inserting its spring and follower into the appropriate longitudinal hole. Place the extractor's leg against this follower, and push it downward and to the rear until it latches in place.

Widen the slot in the bottom side of the slide enough to allow the barrel and barrel retainer to pass through it. Start this wider portion just forward of the breech block face, and make it just wide enough to clear the barrel retainer, and at least .600 inch long. Cut two slots into the slide's center lines, one on top beginning at the front edge of the ejection port, and the other on the bottom just forward of the magazine opening. Make these slots the same size and shape as the lugs on the outer edges of the barrel retainer. The barrel and receiver must mate solidly and rigidly; a close fit here is imperative.

Begin the last assembly step by placing the recoil spring around and over the barrel. With the slide in its proper position inside the receiver, insert the barrel and spring muzzle first through the bottom slot in the receiver and slide. Then, with the barrel retainer lugs mating in their respective slots, the muzzle cap is screwed tightly in place,

Retract the slide by grasping the checkered "ears" at the slide's sequence cocks the gun and chambers a round. Take all possl-

rear end, pulling the 9llde to the rear, then releasing It. This ble precautions when you llrst test-fire the pistol.

locking the assembly firmly together. The slide-receiver unit is placed in position in the frame, and the takedown lever locked.

The pistol is now ready for its first test firing.

Unless you are a fool, you will take certain safety precautions during this first test. For example, it is a good idea to tie or clamp the pistol to something solid while it is fired forthe first time, instead of hand-holding it. Be warned that this may cause considerable damage to the gun if it is not secured correctly, so be careful. Once it is mounted, the trigger may be pulled the first time by means of a string or wire, so you can stand away from it in case something malfunctions.

Load a single round into the magazine first, and work the slide to chamber the round. Then using whatever precautions you deem necessary, fire the round. If everything works properly when the trigger is pulled, the gun will fire and eject the empty case.

If it does not fire, the hammer spring is too weak or the firing pin spring too strong. Try a stronger hammer spring first. If the empty case is not ejected, the recoil spring is probably too stiff. Cut one coil from it and try again. If it still does not eject, cut off another coil. Repeat until proper ejection is achieved.

After the first successful firing, examine the fired case carefully for signs of splitting, cracking, and stretching. Does the firing pin indentation appear normal? Compare the fired case to an unfired one. Did the dimensions change significantly? If you are satisfied that they did not, the gun can be test fired again for semi-automatic functioning.

Load two rounds into the magazine and test fire again. With the first round chambered, the pistol should fire only once. It should then eject the empty case and chamber the second round. When the trigger is then released and pulled again, the second round should fire, repeating the cycle.

If the second round fires as the slide returns forward without the trigger being pulled a second time, the firing pin spring is too weak or the disconnector is too short. A disconnector that is too short allows the trigger bar to remain in engagement with the sear. Try installing a stiffer firing pin spring first. If the second round still fires automatically, remove a little metal from the top edge of the trigger bar until it clears the sear when the disconnector is depressed.

When the pistol fires two rounds satisfactorily, try firing a full magazine through it. Cut and perhaps bend the magazine lips and feed ramp slightly until cartridges feed smoothly and positively from the magazine to the chamber.

Adjust the sights by moving the front sight laterally in the direction where the point of impact is desired. Move the sight blade by tapping it gently with a hammer and punch. Vertical adjustment requires filing the rear sight notch deeper to raise the point of impact, and filing the front sight down to lower it.

As soon as the gun operates smoothly and properly, discontinue firing it, disassemble it, and start the heat treatment of its parts.

Which brings us to the next chapter . . .

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