.500" I-.840" BOTTOM
MAGAZINE ADAPTOR USED WITH COMMERCIAL LOWER RECEIVER
.125" SPRING GUIOt SILVER-SOLDERED IN PLACt
MAGAZINE LATCH, SHOP-MADE RECEIVER
Rent rec&hw motinHng hrackrt shown, alter which close-fitting pins arc pressed in the. holes to hold the ejector in place.
The magazine latch is cut to shape from 1/4 inch flat stock. The slot and spring pocket are milled in the front face of die Mock, and the pivot pin hole is drilled through hoth parts again, simultaneously. The latch should be made slightly-longer than shown in Diagram £34 to allow lor proper fitting during assembly.
It should be obvious that if the shop-made receiver with the short magazine opening is used, the filler block is not used and the alternate magazine latch shown is used instead. I Tie same sheet metal ejector is used; however, the slot to accept it is milled into the receiver and the part silver-soldered in place.
Gcvnpcment jxj/Js used in adopter
Adapter in place. (Note ihul origi/iuf magazine fotch limii< depth of magazine insertion.)
EJECTOR, SHOP-BUILT RECEIVER
EJECTOR, SHOP-BUILT RECEIVER
When llie pistol version is built. a plug, or cap- should be made up to screw into the receiver opening, taking the placc of the butt stock mount. If used as an open holt version, a single recoil spring guide is mounted in ihe center of the cap. This is done by drilling a 1/4-inch hole through the center of the cap and silver-soldering a suitable length of 1/4-inch drill rod in place. The inside of this cap is bored out, as shown in the drawing, to reduce weight. Ihe knurled band on the largest diameter flange not only adds to the overall appearance but provides a gripping surface to aid in installing or removing the part.
When used as the closed bolt version, the rap ik made lo the same overall configuration and dimensions except that the recoil spring guide is omitted. This version requires the same guide, made for two springs* as used in the short-bolt rifle version. This one is made by drilling two . 156-inch diameter holes, which match the width of the spring holes in the bolt, through a thin plate of 3/16 inch flat stock. Ihe ends of two matching lengths ol 5/32 inch diameter drill rud are inserted in these holes and silver-soldered in place.
In my prototype gun, I used two military M I Carbine action springs in the closed-bolt version.
These are tori long in their original stale and must be cut oil. a little at a tune, until the bull will open far enough to pick up cartridges from the magazine. I cannot tell you exactly how long these springs should be since varying dimensions, such as the depth of the holes in the bull, and varying thickness of the wire used in the springs will have an effect.
lor the open-bolt version. 1 used a spring obtained from an auto parts store. 'Jhis one measures .375 iru.h iri diameter, is wound from .050-diamcter wire, and was originally 7/12 inches long. This one too was shortened, a little At a time, until tho action wotdd open completely. As with ihe closed-bolt version, this is strictly a "cut and try" proposition.
Extractors arc identical for all three versions. L'ach should be cut from a better grade of material than common shoot motah duo to the laci that the hnoked end must jump over the rim of each and every cartridge fed through the gun. Needless to say, if soft material is used the part will wear rind drlorm rapidly. I eal spring material can be milled to the required 1/8-inch thickness, or a thin slice can be cut from the end of an axle. Do not neglect this if yon export to use the gun extensively. As with most other small parts, this
.156" DIA. SPRING GUIOES
RECOIL-SPRING GUIDES, CLOSED-BOLT VERSION
EXTRACTOR SAME FOR BOTH BOLTS
MADE FROM .125" THICKNESS, hEAT-TKf-ATABLE STEEL. HOOK SHOULD BE MADE OVERSIZE AND FITTED TO SNAP OVER THE CARTRIDGE RIM DURING ASSEMBLY.
part should he made slightly oversize and dressed to exact fit during assembly.
If ihe closed-boll configuration is adhered to, commercial firing mechanism components, which include hammer, trigger, disconnector, safety, and necessary springs, are available from commercial and surplus parts sources. These are available at attractive enough prices to make it more sensible to buy them than to build them. Unfortunately, several of the surplus parts suppliers got the idea in their heads that they could rip off consumers by doubling, or sometimes tripling, the price of these small parts when the assault weapons ban went into effect. This, of course, didn't work out since there were many more such patts available than there was demand for them. As a result, prices have again returned to normal and should remain so for years to come. An example of this is that all required firing mechanism parts can he obtained from dependable parts suppliers such as Quality Pans Co. in Windham, Maine, for around $40. These arc new parts, and Quality Parts ships promptly, without any B.S. or excuses.
.067" PIVOT PIN HOLE SHOULD BE DRILLED THROUGH BOLI AND FXTRACT0R SIMULTANEOUSLY.
Ihc open-bolt version will require manufacture ol a sciir, trigger, anil disconnector. Ihese are designed to interchange with the closed-bull parts, using ihe existing pivot pins and pin holes, with no change in the lower receiver. This system uses a combination trigger bar and disconnector, which is hinged to the sear. The lower end of this part engages a projection protruding from the lorward end of the trigger. Consequently, when the trigger is pulled to the rear the scar is pulled downward, out of engagement with the boll, allowing the holt to travel forward, pushing a cartridge from the magazine into the chamber. At ihe forward end of the bolt stroke, the firing pin crushes the primer, causing the round to fire. At this point, a combination of recoil and gas pressure causes the bolt to move to the rear, ejecting the lircd case in the process, where it is again caught by the sear and held in the rearward, or cocked, position until another pull of the trigger causes rhe cycle to be repeated. The ' lump," or projection, at the top of the trigger bar is depressed by the forward-moving bolt, which moves the lower, hooked end of the bar out of engagement with the trigger. Ibis requires allowing the trigger to move lorward again be I ore a subsequent shot can be fired.
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TRIGGER (OPEN BOLT)
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