Full Auto Ruger Mini-14 Conversion Manual 9997736826, 9789997736826

Citation preview

FULL AUTO

RUGER MINI-14

FULL AUTO CONVERSION MANUAL

FULL AUTO

RUGER MINI-14 FULL AUTO CONVERSION MANUAL

Full Auto

Ruger Mini-14 Conversion Manual WARNING

!

The legal construction and possession of a fully automatic weapon is controlled by the Bureau of Alcohol, Tobacco, and Firearms division of

the

U.S.

Treasury

Department.

Proper application to the B.A.T.F., authorization, and permission must be secured before

constructing

this

or

any

other

similar

Local and state laws vary and may restrict ship of this or similar type weapons.

device. owner-

Severe penalties are authorized for violators of these laws. Minuteman Publications offers this information for academic study of firearms design and disclaims any responsibility or liability for the improper or illegal use of this or other similar devices.

Table

Of

Contents

CONTENTS

PAGE cececiisliciincccaccccccivsiictssss

cunt

......ccccccccccceccccccrscece

FY

Chapter 1 General Description And Mode Of Operation Semi Automatic .....ccceeceeeeeeeerereeees

1d

Chapter 2 Genera] Description And Mode Of Operation Full Automatic ........ mrelelelateteleratetetetsietelartal=

21

Chapter 3 Modifications

.......

29

.............

39

TNCPOdUCEION

Index

Blueprint

Chapter 4 New Parts Chapter

To Be Made

To Weapon

To Be Manufactured

5

Material

For

Construction

................

51

Introduction The

purpose

of

this

the necessary blueprints conversion for mation

civilian automatic bursts, The later,

version, weapon being

fully

manual and of

is

to

into MINI-14 RUGER firing of capable controlled

modification basically but

provide

manufacturing inforsemi-automatic the

by

will be consists

the

a fully multiple

firer.

fully described alterations of

stock, and a sear group, and to the receiver, also the manufacturing of a disconnector assembly. The weapon can be converted to fire fully autosemi-automatic to back restored be or matic in little more time than it takes to field strip it. This conversion does not provide selective fire capability. It is very reliable and rugged due to its design and manufacture. This

manual

presents

the

necessary

data

that would be required by a machinist or gunsmith to complete all modifications to the gun and Engineers to manufacture the required components. design weapons such as this with a great deal of care, and for successful operation care must also be exercised in the manufacturing procedures to be explained regarding this conversion.

Index

Blueprint 1,

OPERATING SEQUENCE - SEMI AUTOMATIC Hammer A. sear.

cocked,

engaged

trigger

with

hammer releasing is depressed Trigger B. to strike the firing pin and detonate the forward moves sear Secondary cartridge. slightly.

C. The trigger is still depressed. The slide and bolt have cycled rearward causing the hammer to be forced rearward and engage the

secondary

sear.

D. The slide and bolt have cycled forward stripping a cartridge from the magazine. The trigger is released and the secondary trigger the as hammer the releases sear sear engages and holds the hammer, ready for the next firing cycle. 2.

OPERATING

A.

SEQUENCE

Hammer The

sear.

- FULL

cocked,

AUTOMATIC

engaged

disconnector

trigger

with

assembly

is

shown

in position. B.

The

trigger

is

depressed

releasing

the

hammer

to fire

the cartridge.

Disconnector

With the trigger still depressed, the slide C. and bolt have cycled rearward forcing the hammer to engage the secondary sear which had previously moved forward slightly as the slide unlocked the

and

bolt

rearward.

moved

The slide and bolt move forward under recoil D. spring pressure. Just before the slide stops it makes contact with the tripping lever, forcing it forward. As the tripping lever pivots the disconnector

and

releases

the

forces

the hammer

secondary

to fire

sear

another

rearward

Pin-Disconnector Assembly

and

Pin-Disconnector, ment

Secondary

Clip-Retaining-Disconnector

Fixtrue-For machining.

holding

cartridge.

The trigger is released allowing the hammer E. The firer has only to engage the trigger sear. to depress the trigger to resume automatic fire.

3.

4.

PARTS

TO MODIFY

A.

Receiver

B.

Slide

C.

Secondary

0 .

Stock

PARTS

Sear

TO BE MANUFACTURED

A.

Screw-Pivot,

Tripping

8.

Tripping

Lever

C.

Bushing,

Tripping

Tripping

Lever

Lever

"

secondary

Lever Sear

Engage-

Pin

sear while

General Description And Mode Of Operation—Semi Automatic SPECIFICATIONS MINI-14

RUGER

The

operated,

gas

a

is

rifle

.223 the for chambered firearm semi-automatic (5.56mm) caliber U.S. military and commercially magazine box is It cartridges. manufactured 10, 5, hold to available magazines fed with A 75 round rotary 20, 30, and 40 rounds each. drum magazine is also available. mechanical basic its takes MINI-14 The properties from the U.S. military Garand family a scaled-down resembling somewhat of weapons, the

military

M-14

changes’

from

is

used

rifle.

steel

molybdenum

chrome

Hardened

and firing mechanisms. breech the in reliability is provided through the use wire coil springs. MINI-14

The its

introduction

One

governments

the

of is

its

and

law

Many

1972.

are

reasonable

since

enforcement

choosing

the

applications.

general

contributing

Spring of music

popular

very

become

has in

specialized

for

popularity

12

some

and

agencies MINI-14

the

of

parts

minor

several

had

have

MINI-14

internal

The

externally.

M-14

factors cost.

1982

to

its

prices

of approximately for $350.00 and investment. jood 540.00 required

$100.00 it

for

to

to

full

many

$285.00 for the blue version it a gun make stainless the the approximate to Compared for a Colt AR-15 and an extra inflation

with

people

is

RUGER

the

convert

to

parts

the

for

$150.00

auto,

choice

a practical riddled

budgets.

OPERATION The of

the

semi-automatic

following

steps:

inserts

1.

The the

firer rifle.

2.

The

slide

it

stops,

is and

mode

a

then then

is

of operation

loaded

consists

into

magazine

pulled

rearward

released

sharply

until thereby

forward under propelled the bolt, allowing recoil spring tension, to strip a live round during it chamber and magazine the from forward movement. As the bolt face contacts the breech of the barrel, a camming surface in the slide rotates the bolt forcing two locking lugs into matching recesses in the receiver. This will prevent the bolt from high initial the during rearward moving pressure

following

detonation

of

the

car-

At this point, the hammer is cocked tridge. and held back by an engagement between the sear notch on the trigger and the hammer. (See drawing # 1A)

3.

the

secondary

The

hammer,

spring,

is

firing

pin

sear under

moves

forward

pressure

from

propelled and

forward,

detonating

(See

drawing

# 1B)

and

locked

until

The

slightly.

striking the

bolt

the

cartridge.

will

stay

chambered

the

hammer

the

closed

pressure

a small level, and until to a safe drops barrel the from is vented of gas amount through the gas block blowing against the front of the slide with enough pressure to unlock the bolt (by reversing the camming action).

The

slide

carrying

with

it

the

spent

bottom hammer dary

which

bolt

cartridge

move

then

will

the

and

ejects

which

will

the

hold

extracts it.

The

forces the the secon-

of the bolt contacts and rearwards until it engages sear

rearward,

hammer

back.

spring As the recoil # 1C) (See drawing compression overtakes the recoil inertia, the slide will reverse and move forward, carrying the bolt which again strips a live cartridge from the magazine and forces it into the chamber. When the trigger is released, the sear engagement with the hammer will change. The trigger sear engages the hammer just before the secondary sear disengages from the hammer and moves rearward to its original position. By this time the bolt is locked into the receiver again and

pressure

applied

to

the

again release the hammer to tridge and repeat the cycle.

forward been moved the safety having With to "off", the firer then depresses the trigger which disengages the hammer from the trigger In this same motion of the trigger, sear.

15

trigger

fire

the

will

car-

$l *

NOTE-BOLT

&

HAMMER COCKED, SECONDARY SEAR

SLIDE

NOT

SHOWN

ENGAGED WITH TRIGGER IS NOT ENGAGED.

SEAR,

TRIGGER SEAR (INTEGRAL WITH TRIGGER)

OP.

DRWG.

SEQ.

NO.

SEMI-AUTO

1-A

ROTATION

emmy

TRIGGER STILL DEPRESSED: RECOILING BOLT ENGAGE SECONDARY SEAR. TRIGGER SEAR IS STILL FORWARD.

FORCED

TRIGGER IS DEPRESSED. HAMMER IS RELEASED AS TRIGGER SEAR AND SECONDARY SEAR ROTATE FORWARD SLIGHTLY,

$l bl

OP.

DRWG.

HAMMER

OP.

DRWG.

1-B

1-C

TO

AUTO

SEQUENCE-SEMI-AUTO

NO.

REARWARD

SEQ.-SEMI

NO.

SEQ.-SEMI-AUTO OP.

BOLT & SLIDE (NOT SHOWN) HAVE CYCLED FORWARD. TRIGGER HAS BEEN RELEASED, SECONDARY SEAR & TRIGGER SEAR PIVOT WARD. HAMMER ENGAGES WITH TRIGGER SEAR AS SECONDARY SEAR DISENGAGES FROM HAMMER. DRWG. NO. 1-D

20

i. 2

ROTATION

REAR-

2

Automatic

Operation-Full

Of

Mode

And

Description

General

of description the into getting Before please mode, full-automatic the in operation overlay conver-

an shows # 2A which to drawing refer of disconnector assembly required for this

better

This will help the reader sion. the sequence of operation.

understand

When the trigger is depressed, the trigger allowing the hammer sear and hammer disengage, to strike the firing pin and detonate the carThe slide unlocks the bolt and recoils tridge. The backwards, extracting the spent cartridge. firer still has the trigger depressed. The hammer is

caught

as

the

drawing

and

bolt #

held

2C)

by

back

completes Recoil

its

the

rearward

spring

secondary

sear

travel.

(See

pressure

reverses

then strip a live which wil] the bolt travel cartridge from the magazine and begin to chamber and is fully chambered As the cartridge it. as the bolt starts to rotate to lock, the slide It is at this time is still not fully closed. lever and forces a tripping it contacts that This forward movement of the tripping it forward. lever produces a rearward movement of the disconnector which is attached to the secondary sear. This movement forces the secondary sear rearward, the hammer to strike the firing pin releasing During the time necessary for the seconagain.

21

22

2-A

Ay

NO.

= H

SEQ.-FULL-AUTO

& 9

OP.

sequence

is depressed the magazine. trigger sear back in the by the firer firing.

DRWG.

firing

will repeat as long as the trigger and as long as cartridges are in When the trigger is released, the will engage and hold the hammer cocked position. Applied pressure to the trigger will resume automatic

1-A)

This

and the bolt safety to the

#

# 2D)

to

reached

DRWG.

drawing

have

AS

(See

will

(SAME

furthermost forward travel be fully locked, ensuring

hammer

the

for

slide

HAMMER IS COCKED, ENGAGED WITH TRIGGER SEAR DISCONNECTOR ASSEMBLY IS IN PLACE SLIDE IS FORWARD THE RADIUS c UT IN THE SLIDE BARELY ENGAGES THE TRIPPING LEVER, THEREBY APPLYING A SLIGHT REARWARD PRESSURE ON THE SECONDARY SEAR

the

PIN

pin,

PIVOT

and

disengage

firing

SCREW PASSES THROUGH STOCK & TRIPPING LEVERATTACHES TO RECEIVER (#6-32 THD.)

firer.

the

PIN ENGAGES & LOCKS INTO S EC. SEAR

its will

to

sear

& SLIDE

strike

CONTACT AREA TRIPPING LEVER

dary

1. 2.

°){

l/

=

REARWARD.

AUTO

TOP OF TRIPPING LEVER HAS MOVED

SEQ.-FULL

2-B

THE

TOP

CAUSING

SCREW.

OF

TO

LEVER

LEVER

TRIP.

TRIP.

MOVES

PIVOT

PIVOT

REARWARD.

ON

OP.

SEQ.-FULL

AUTO

TRIGGER IS STILL DEPRESSED-TRIGGER SEAR STILL FORWARD. SLIDE AND BOLT ARE IN FULL RECOIL. AS THE SLIDE MOVED REARWARD, THE CONTACT BETWEEN THE SLIDE & TRIPPING LEVER CEASED. SPRING PRESSURE ON THE SEC. SEAR MOVED IT FORWARD WHERE IT THEN ENGAGES & HOLDS THE HAMMER BACK. THE DISCONNECTOR DRWG. NO. 2-c ASS'Y MOVED PORWARD WITH THE SEC. SEAR, : :

«

Nam

OP.

TRIGGER IS DEPRESSED-TRIGGER SEAR DISENGAGES FROM HAMMER, HAMMER ROTATES FORWARD TO STRIKE BOLT. (NOT SHOWN) SLIDE IS STILL FORWARD, ENGAGED WITH TRIPPING LEVER. SECONDARY SEAR REMAINS REARWARD WHILE SLIDE IS FORWARD. DRWG. NO.

SEC. SEAR STATIONARY

w WNhne

1. 2.

9

re

rei

)

ee

te ee

et

ee

PIVOT

ENGAGES. REARWARD PRESSURE APPLIED TO THE TRIGGER WILL RESUME FULL AUTO FIRE.

OP.

SEQ.-FULL

AUTO

CARTRIDGE INTO THE TRIGGER SEAR TO

PIN

OP. SEQ.-FULL AUTO

DRWG. NO. 2-E

BOLT ARE MOVING FORWARD-FEEDING A LIVE TRIGGER HAS BEEN RELEASED, CAUSING THE THE HAMMER AS THE SEC. SEAR DIS-

THE CARTRIDGE.

TRIGGER IS STILL DEPRESSED. ‘TRIGGER SEAR STILL FORWARD. FORWARD MOVEMENT OF THE SLIDE PIVOTED TOP OF TRIP. LEVER FORWARD AS CONTACT WAS MADE. THIS CAUSES REARWARD TRAVEL OF DISCONNECTOR WHICH MOVES SEC. SEAR REARWARD ALSO. ‘THIS DISENGAGES THE HAMMER TO STRIKE THE BOLT & FIRE DRWG. NO, 2-D

THE SLIDE AND CHAMBER. THE ENGAGE & HOLD

rt

es

3 To

Modifications

Made

Weapon

To Receiver

Be

= Drawing

# 3A

Machine lug off of lower right side of receiver flush with adjoining surface as indicated in the drawing. This is required to provide clearance for or assembly.

A

slot

as the

operation

machined

into

of

the

indicated. This provides tripping lever which will

this A

is

the

flange.

#

6-32

threaded

hole

jis

the receiver as indicated of the Disconnector assembly

screw,

Slide

- Drawing

the

disconnect-

upper

flange

clearance for extend through

machined for with

into

attachment the pivot

# 3B

A single cut is made into the slide as indicated on the drawing. This will provide Clearance for the top of the tripping lever, and also establish a contact point which the tripping lever engages during the forward movement of the slide.

28

3.

Secondary

Sear

- Drawing

# 3C

The secondary sear is machined in such a manner as to provide an easy and quick method of assembling the Oisconnector-Secondary Sear Pin to the Secondary Sear. The pin is inserted through the large hole in the secondary sear until the small diameter of the sear,

pin matches the slot in the secondary Slide the pin over in the slot until

the smaller of the two holes is reached, and then pull the pin out until it firmly locks with the secondary sear. The plastic retaining clip can then be attached to the small diameter of the pin to prevent the pin and sear from accidentally coming apart. Use the fixture previously described when machining this part.

Stock The

- Drawing

# 3D

stock

must

be

ance for tolerance

the for

disconnector assembly. The these cuts are not critical,

machined

to

provide

clear-

as long as adequate clearance is provided. However, the location of the pivot screw hole should be matched as closely as possible with the # 6-32 threaded hole in the receiver. This can be determined by scribing a vertical line on the receiver through the center line of the # 6-32 hole up onto the side of the flange. With the receiver in the stock, this line can be transferred back down on the outside of the stock to establish its vertical centerline. The horizontal centerline can be located by measuring the

distance from the bottom of the flange to the center of the # 6-32 hole, on the receivWith the stock and receiver assembled, er. measure down from the bottom of the flange on

the

outside

point

screw.

of

the

distance.

measured to

be

machined

stock

This to

and

scribe

establishes accept

the

the

the pivot

OPERATION

~

#

#

OPERATION “~~

#

(BOTTOM

(RIGHT

2

a

RIDGE (LOWER) SURPACE ‘A'

e

3/16"

(.1875)

- Raut # 36 (.1065) -32 N.C.

- MILL WITH

VIEW)

3 - MILL

1

VIEW)

SIDE

OPERATION # 1

OPERATION

we

A

OF

SLOT

2

WALL

WALL

FULL

SCALE

1

275

.450

AND

UNTIL

DRWG.

LONG

NO.

THREAD

FLUSH

——~ 265 eee

RECEIVER-MODIFIED

FLANGE,

RECEIVER

RECEIVER

ge

Le |

#50

OPERATION

OS

THROUGH

THROUGH

OFF

a

-

OPERATION

Vaé

3-A

125 (RIGHT

(BOTTOM

5

HAND

VIEW)

VIEW)

SLIDE-MODIPIED PULL

SCALE

DRWG.

NO.

3-B

AREA

Uf)

SHADED

SVSY

DIAGONAL

MODIFIED

REPRESENTS

LINES2

REPRESENT

STEEL

PORTION

3

3TOCK

OF

LINE

STOCK

oR

450

4.21

3.850

400

32

.

RIGHT SIDE VI EW RIGHT STOCK WALL

SL

LOCATION OF THIS HOLE MUST MATCH # 6-32 HOLE IN RECEIVER

ONLY)

1 '

ABS

a

I

oe --32]

|

eo

|

ry

|

TOP VIEW

STOCK ASSEMBLY | PULL SCALE | DRWG. NO. 3-D|

MILL AND

SLOT

.093

WIDE

BETWEEN

3/16"

HOLE

-

CENTER

ON

1/8"

4

HOLE

LINE

To

Parts

New

Screw-Pivot,

Manufactured

Be

Tripping

Lever

-

Drawing

#

44 This the

DRILL 3/16" (.1875) HOLE

screw will act tripping lever.

as a pivot point for It is designed with

against out bottom will that shoulder a the receiver when installed. This will prevent binding between the tripping lever and the receiver.

THROUGH

DRILL 1/8" (.125) HOLE THROUGH

Tripping

The of

top the

Lever

of

- Drawing

this

slide

lever

each

# 48

will

time

contact

the

means of a pivot in the the forward movement at causes the bottom of

gun

a portion cycles.

to move rearwards. It is by this that rearward movement is provided to

gage the secondary of the slide. Bushing,

Tripping

sear

Lever

By

center of the lever, the top of the lever the tripping lever during

- Drawing

each

action disen-

cycle

# 4C

This bushing iS permanently attached to the tripping lever by flaring the small end after inserting it into the lever. It

8

SECONDARY

FULL

SCALE

SEAR

DRWG.

NO.

3-C

is

through

mounts

this

the

Disconnector

This

part

lever

is the

to

that

the

- Drawing

linkage

the

pivot

screw

receiver.

Fixture-Secondary # 4H

# 40

through

movement of the tripping to the secondary sear.

assembly the disconnector and prevents disengaging from the secondary sear.

which

lever

the

is

rearward

transferred

ig

Pin-Disconnector

The

pin

and

attaches

Tripping

Tripping

the

Lever.

It

Lever

- Drawing

Disconnector also

acts

to

as

a

of

the

secondary

it.

the pivot

for the two parts. The pin is flared on both ends when installed to prevent the disconnector and tripping lever from coming apart.

6.

Pin-Disconnector, - Drawing # 4F

Secondary

Sear

Engagement

This pin is permanently attached to the disconnector and its purpose is to engage the

is sear

secondary

applied is

also

sear.

to

the moved

Clip-Retaining, # 46

When

movement

the

secondary

rearward.

Disconnector

The

plastic

clip

ter

of

disconnector

the

rearward

disconnector,

attaches

to

Pin

the

-

Drawing

small

secondary

sear

Machining

-

Drawing

The secondary sear has irregular shape not suitable for clamping in a mill vise. This fixture will securely hold and prevent movement

5.

Sear

from

diamepin,

4l

sear

while

machining

— 310 1040 cls

‘

3/16"

K}

ve

ras

RADIUS

-

BOTH

YS

|

.

ais

.670

=

2

1.085

_———

iL

a

- 400

ENDS

# $32

THREAD

6

_

z

309

;4

o)

a

aA

B

— —»

[7

|

1875

.375

Ud7

J

~~

1/16"

—

(.0625)

CHAMFER .020 x 45°, BOTH HOLES (ONE SIDE ONLY)

SCREW-PIVOT

42 SCALE

2X

DRWG.

'A'

= DRILL

7/32"

'B'

- DRILL

1/8"

4 NO.

4-A

(.2187) (.125)

THROUGH THROUGH

TRIPPING LEVER SCALE

2X

DRWG.

NO.

4-B

“7

5.217 -

|

)

—4,7.

3.785

(aA pe DRILL PIVOT

/|

1/8" PIN,

i

4

LP, CHAMFER '‘R*

11/64"

- DRILL

(.1718)

| 375

>)—

FOR (.125) THROUGH LEVER & TRIPPING DISC.

LZ»! —— .020 x 45°BOTH HOLES, THROUGH

FOR

SECONDARY

-0625 ONE SIDE ONLY SEAR

ENGAGEMENT

PIN

DISCONNECTOR 44

FULL

SCALE

DRWG.

NO.

4-D

i ./875

I.D.

PIN

CAN

BE

[J] MADE

|

,250

oR 1/8"

DIA.

ROD

DRILL

OR EQUIVALENT

.2/8

rs—

FROM

Q_yes

0.0.

PIN-DISC. 2X

TRIPPING | DRwa.

LEVER NO.

4-E

=

~ On Q

SCALE

&

-085 ./23 . 088 205°

STSHING C MREDDIRG TRIER SCALE

2X

| DRWG.

NO. 4-c

0

el} PIN-SEC. SEAR ENGAGEMENT SCALE 2X | DRWG. NO. 4-F

S

w

4

#29

ele

yee

-

Je

-085

tt : -250

}

(.136)

ence{RE

THROUG}

DRILL

; 4 .750

.

qQ

“e

—

650

it

it

Ld

‘

(|=

=

| 8 |

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&

=

a

a

: =

a

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v0

H

Sl

Oo]

|_|

bed

*—

ae

wa

;

.300

ono

oe oh

San

a

79

|

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~~

Ww

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Bis 2D

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teca

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oe]

mt

te

3

ses

=

3.0

Bo

22

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£=

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2

s

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BN

an tt

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=

2

* ie)

‘ino

g

&°

Ne

8h aS

-

DH

TOP

68

N

.

== Ui

WD

R

|

‘

bas

PIXTURE

| DRWG.

- SEAR NO.

4-H

x 1/2", SECONDARY

STEEL

sine

8-32 HOLD

3/qn

3

:~

SEAR IN FIXTURE WHILE MACHINING HOLES & SLOT

x

SCREW-# USED TO

3/h"

FIXTURE MADE OP

FULL SCALE

2.

TF

gyN

4

IPE

1

Ww

S

250.350

~>,

ae

4-I NO.

DISCONNECTOR ASSEMBLY

| DRWG.

Lever

This part can thickness sheet

INSERT PINS AS INDICATED BY ARROWS, FLARE THE PARTS PROTRUDING TO LOCK PINS IN PLACE.

Bushing,

HERE

Lever

Tripping

This screw can be either purchased or manufacUnhardened tured from a suitable material. drill rod would be fine for this application since it machines well, and is easily obtainable.

Tripping

FLARE

Construction

For

Material

Screw-Pivot,

FULL SCALE

PLARE HERE (USE CENTER PUNCH) FLARE

FLARE

5

be made metal.

from

1/16"

standard

Lever

Tripping

This part can be Drill rod as used

made from almost any steel. in #1 would be very good.

Disconnector The

same

material

for construction

used

of this

5

for

part.

#2

can

be

used

5.

Lever

Tripping

and

Pin-Disconnector

#1

used for The same material be used to make this part. Secondary

Pin-Disconnector,

Use for

ie

the

Clip-Retaining, The any

of

material type

of

this

for

#3

can

Engagement

#3,

and

#5

part.

Disconnector

used

#1,

as

material

same

construction

Sear

and

this

semi-flexible

Pin part

can

plastic

be almost such

as

requirement only The or NYLATRON. DELRIN is that this part be flexible or “springy” its it can clip onto and retain so that position on the pin, # 4F.

Fixture-Secondary Any for

Sear Machining

type of steel or this application.

aluminum

can

be

used