Micro Uzi Machine Pistol Semi-Auto Modification Manual

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MICRO UZI MACHINE PISTOL

Semi-Auto

Modification

Manual

MICRO ~ MACHINE Semi-Auto

UZI PISTOL

Modification

“T

Manual

Historical

Although successful semi-automatic pistols appeared on the market prior to the turn of the century, the machine pistol is uniquely a product of the Twentieth Century, and specifically of the era between the World Wars. The most famous machine pistol is, of course, the Mauser, which has led many to believe that it was the first of the breed. However,

the Spanish

Astra actually predates the Mauser by some time. Although the two appear to be almost identical externally, internally the differences are significant with the Astra featuring much simpler construction and manufacturing techniques. Both the Astra and the Mauser were available with wooden buttstocks which also served as holsters. When attached to the grips of the weap- — ons, these buttstock/holsters were supposed to turn them into short barreled carbines. While this concept may have intrigued the designers, it was hardly new. Detachable buttstocks had been made for percussion model Colt revolvers during the mid-1800’s and, like the machine pistol stocks, had

seen only limited success in turning these handguns into longer-ranged weapons. While it’s easy with the benefit of hindsight to look at machine pistols and say that they were designed to solve a nonexistent problem or that the breed was doomed to an early demise because

Background

the basic principal is unsound in the first place, the concept wasn’t really all that ridiculous in theory. This is especially true when one considers that the submachine gun had been introduced into combat just a few years previously, right at the end of World War I. The SMG had been conceived as a method of bringing the firepower of automatic weapons into the trenches where the long range, bolt action Springfield, SMLE Enfield and Mauser 98 battle rifles were proving impractical due to their length and slow rate of fire. If the SMG made the machine gun’s firepower more portable, wouldn’t a machine pistol accomplish this purpose to an even greater degree? Indeed, the German MP1918I, which was called a machine pistol, was actually an SMG in every sense of the word. While it bears a much closer resemblance to modern day semi-auto carbines than to any of the sub guns with which we are familiar today, it still deserves

mention as being the ons which has become important genre in the Although the role been clearly defined

first in a new breed of weapan ubiquitous and extremely field of combat weaponcraft. of the SMG in warfare hadn’t when hostilities ended in

1918, its performance to date had been sufficient-

ly adequate to warrant further development in several European countries as well as in the U.S., where the famed Thompson was born.

MICRO UZI MACHINE PISTOL

pistol was, indeed, an attempt

duced in 7.63mm Mauser, with the latter also being

to scale down automatic weaponcraft even beyond

If the machine

produced in 9mm Parabellum during World War II. While the popularity of the machine pistol has declined steadily almost from the day of the con-

the SMG

stage, it was pretty well doomed to fail-

ure since its high cyclic rate in the full auto mode made it virtually unmanageable. As a “trench broom”

it might have been effective, but it would

be safe to say that in the vast majority of firefights

in which machine pistols have figured over the past 50° years or so, they were (or should have been)

employed in the semi-auto mode. These compact automatic weapons may also have been envisioned as a means of eliminating both the sub gun and the pistol from the ordnance

inventories of the various European powers. Since SMG’s used the same ammo as the issue pistols, wouldn’t it make sense to design one weapon

to

do both jobs? The same argument was heard in the U.S.

during

tended

the

1930’s,

to replace

with the M1

both the Thompson

carbine

SMG

in-

and

cept’s inception, the SMG has, on the other hand,

steadily gained in popularity. Although many sub gun designs were produced following World War I, it remained for the Spanish Civil War of the 1930’s to prove their ultimate worth as a combat weapon. Just as the poison gas, submarine and airplane of World

War

I changed

warfare

forever,

the sub-

machine gun and dive bomber of the Spanish Civil War again altered fighting tactics less than a generation later. Both Germany and the USSR used the fighting in Spain to test new weapons and concepts. The sub gun proved invaluable in house to house fighting and in forests where ranges were short and targets might not be visible for more than a second or two. On September 1, 1939, warfare changed again

the Colt M1911A1 pistol. While the M1 received a much kinder fate than the machine pistol, and is indeed a popular weapon with sportsmen today, it’s interesting to note that both the SMG and the military issue sidearm are still with us today, while the machine pistol is presently relegated to the rank of a collectible oddity. Although they never gained the world-wide acceptance as military and police weapons which

measured in exception of very quickly prepared for

their

machine

bor on December 7, 1941, yet we were able to turn

pistols did meet with some success in Asia and

the tide and start rolling the Japanese war machine back toward the Land of the Rising Sun almost six months to the day later in the Battle of Midway. Even though Japanese troops actually occupied more of China and Indochina when surrender came in 1945 than they had at the end of 1941, the handwriting was on the wall in the summer of 1942. The Battle of the Bulge, often thought of

Latin

designers America.

must Indeed,

have

envisioned,

as these words are being

written, Brazil is finally phasing out the last of its police issue Mauser Model

1932’s in favor of

a home grown sub gun. Mausers and Astras were both popular among the private “armies” of various Chinese warlords prior to World War II, and more than one Chinese copy of the Mauser has been found, chambered in .45 ACP. In addition

to the Mauser and Astra MP’s, Star also produced one known as the Model M during the 1930’s. It bears a strong resemblance to the standard Colt Government Model but has a select lever on the right side of the slide. The Star was sold to Nicaragua in limited quantities. It was produced in .45 ACP and may have been produced in other calibers as well, while both the Astra and Mauser were pro-

as Hitler introduced the world to a new word — blitzkrieg, or lightning warfare. While the stalemate

in the West had dragged on for months on end in World War I, stalemates of World War II could be

days or weeks at the most. With the the fighting in Russia, events moved during World War II. The U.S. was illwar when Japan attacked Pearl Har-

as a stalemate to the American advance to the Rhine, lasted less than a month before GI’s were

able to recapture all the territory they had lost to superior German forces. From Egypt and Morocco in North Africa to Guadalcanal

and

Leyte

in the Pacific, and

on

to

Monte Cassino and Omaha Beach in Europe, submachine guns proved their worth to the Allies in battle after battle and skirmish after skirmish.

MICRO UZ! MACHINE PISTOL

They were ideal for the close quarters fighting in the jungles of Indochina (where they would still be fighting 30 years later in a new country called Vietnam) and for house cleaning operations in

tax: Some

of these aftermarket

accessories have

since been classified as machine guns in themselves by the BATF and have thus disappeared from the market. For more complete details, along with the

Fortress Europe. Early in the war, the venerable Thompson was modified somewhat to speed up production and

weapon that is as near to factory original as you can possibly get, see Firepower Publications’

reduce the cost of manufacture. This was only a start in the direction that SMG’s were to take

Modification Manual.

over the course

of the next 40-odd years as de-

signers constantly sought ways to lower the cost, simplify production, and make the guns smaller and lighter. One of the first of these “new breed” sub guns was the M3 “Grease Gun” which was extremely cheap to produce, yet quite reliable. It and can still be found chugging away in various trouble spots throughout the world today. Among the more successful designs of the postwar era were the Czech Models 23 and 25 (the only difference being in the stock), which had a telescoping bolt. This bolt was copied by Uziel Gal when he designed the famous Uzi for Israel soon after that nation came into being. The Uzi quickly gained fame for its ruggedness and reliability and is today in such demand that the parent IMI plant in Israel has licensed FN to produce Uzis in Belgium. Although federal law permits individuals to own automatic weapons as long as they comply with all the requirements of the National Firearms Act, certain provisions of the 1968 Gun Control

Act make it impossible for civilians to legally own a select fire Uzi manufactured in a foreign country.

However, the Uzi’s reputation for ruggedness and reliability make it a highly desirable weapon for collectors, survivalists, and other shooting enthusiasts. Recognizing this market, it was inevitable that IMI would introduce a civilian legal, semi-auto

Uzi to the American market. Hardly had this semiauto carbine appeared in 1980 before aftermarket accessories became available for converting it to

select fire. Since the conversions were done in this country, they were legal as long as the owner obtained prior BATF approval. This involved filling out a BATF Form 1 and sending it in along with the BATF supplied fingerprint cards and the $200

conversion

Book

method

No.

With

FP-4,

which

Selective

produces

Fire

a select fire

Uzi Semi-Auto

increased infiltration of PLO terrorists

into Israel, the early 1980’s saw a rising need for a

smaller, lighter SMG with a higher cyclic rate than that of the standard Uzi. Israel Galili, designer of the famous Galil assault rifle, was assigned the project.

He was able to shorten the frame, cover,

bolt and barrel of the original weapon to create the Mini Uzi, which

is a full 3.5” shorter than the

original. Military specifications, designed to meet the needs of Israeli paratroops and commandos, called for a cyclic rate of 1200 rounds per minute. To help control muzzle climb during full auto fire of this lighter weapon, a muzzle brake is incorporated into the end of the barrel. Needless to say, the Mini Uzi has quickly gained

wide

acceptance

among

those who

must

carry an automatic weapon, whether for executive protection duties or on the battlefield. With fully 45% of its parts interchangeable with its full size cousin, the logistics of repair is greatly simplified, a large plus for quantity purchases by military establishments. Not content

to rest on its laurels, IMI intro-

duced the semi-auto Uzi pistol in 1983. This weapon is obviously aimed at the ever-growing civilian market

for military look-alikes. While it is some-

what larger and Parabellum

pistol,

heavier than it does

have

the normal 9mm a lot going for

it. First and foremost, it’s a genuine Uzi and wears all the mystique of that name proudly. The same robust construction and quality of its predecessors is there. Although not intended as a target pistol, it features fully adjustable sights. For the person who owns an Uzi semi-auto carbine or SMG, it offers a

handgun with the same basic operating characteristics, such as magazine and safety locations, etc.

Additionally, all standard 32 and 25 round Uzi

MICRO UZ] MACHINE PISTOL

magazines

will fit the pistol, allowing the owner

the option of increasing his firepower if he so desires by simply using the magazines for his carbine or sub gun. The grip panels are also interchangeable. They have been redesigned on the pistol to improve the shooter’s grip since the weapon has a tendency to point low. Anyone converting it to select fire might wish to substitute carbine or sub gun grips for those which come on the pistol.

While we have commented elsewhere that the tactical application of machine pistols is questionable at best, we certainly can’t argue with the fact that, like all automatic weapons, they are just plain fun to shoot. With this in mind, we have taken a standard Uzi pistol and turned it into the smallest,

lightest select fire Uzi yet — the Micro Uzi Machine Pistol, the latest offering in exotic weapons from Firepower Publications.

The Uzi Assault Pistol Becomes The Micro Uzi Machine Pistol

The various Uzi weapons that are now available

sometimes cause a bit of confusion among weapons buffs. The first Uzi imported into the U.S. was the well-known Uzi submachine gun which was and still is available only to Class III dealers and law en-

forcement

agencies.

carbine with

which

Next

pistol,

are

the Uzi semi-auto

everyone is now

latest two offerings, assault

came

the Mini the

ones

some degree of confusion.

The Micro Uzi complete with folding stock and barrel extension.

familiar. The

Uzi and the Uzi

that

are

producing

MICRO UZI MACHINE PISTOL

The

confusion

centers

around

the

mistaken

idea that the Uzi pistol is simply the semi-auto version of the Mini Uzi SMG. Wrong!

While similar in appearance, design and even sharing a few common parts, the Mini Uzi SMG and the Uzi assault pistol are two distinctly dif-

ferent weapons. The Mini is smaller than the original Uzi SMG

or carbine yet larger than the assault

pistol. At the time of this writing the Mini is only available in select fire to Class III dealers and law

enforcement agencies. It is doubtful if there will be a semi-auto Mini Uzi in the foreseeable future. The

Uzi assault pistol, upon

which our atten-

tion is focused, only comes in the semi-auto configuration. Being a pistol, it is devoid of any shoulder stock,

folding or otherwise.

While

having

the

same basic cross section, it is the shortest of the breed, shorter than the Mini by nearly 5 inches. It seemed only natural to dub our new select fire Uzi pistol the “Micro Uzi”.

iv

The “Micro Uzi" machine pistol is shown here without shoulder stock attached.

Some

Select

Fire

Design

Full auto conversions to the Uzi carbine are so commonplace nowadays that it is only natural to assume that any or all of the methods could be applied to the Uzi pistol. For the trigger housing group this is true. Many of the same parts are utilized, including the ever-present selector block which prevents (until removed) the select lever

from traveling far enough forward to effect full auto fire. The receiver group proved to be the problem area. At first sight it would seem that replacing the bolt with one designed to slam fire from the open position would be enough. Wrong! Due to its extremely short receiver, the firing pin/striker assembly travels a shorter distance under a stronger spring than does its counterpart in the semi-auto carbine. If an

open

firing

bolt

was

used,

the cocked

position would place the bolt face too close behind the top round in the magazine. Thus, an insufficient amount of energy would be available to strip, chamber and fire the round reliably. The only way to effectively convert the Uzi pistol to select fire was to go to closed bolt firing. This entails some rather delicate machining requiring at least a lathe and a drill press with an X-Y

Considerations

milling table. A vertical milling machine would be even better. While it might be possible to file the parts out by hand, it’s a little too Robinson Crusoe for most people. Before proceeding further, study the photos and drawings included herein until you are familiar with the method used. In the trigger housing we have removed the selector travel block and extended the slot where the tang of the selector exits the housing. We also removed and discarded the grip safety. This part, besides its safety function, also

retained the sear and trigger pins. A dual function spring was added that provides the latter function. To provide closed bolt full auto fire, a secondary sear was added. This sear required a trip lever that would activate it just as the bolt reached battery. This sear/trip lever was made up as an assembly to fit just behind the magazine well — in the area formerly utilized by the grip safety. The striker assembly needed an additional sear surface and the bolt required a carefully located camming surface be added. The receiver required two notches be filed to accommodate the new sear and trip lever. The sear surfaces and trip lever were case hardened at the wear points.

MICRO UZI MACHINE PISTOL

Conversion

CONVERSION

Procedure

PROCEDURE

Disassembly of the Uzi pistol is identical to that of its older brothers and the owner’s manual

which accompanies it contains sufficient information for that purpose, so we won’t covering that phase of the operation.

waste

time

Before anything is done to the weapon itself, it is suggested that you first construct the secondary sear assembly. This is one of the most difficult parts and if you bog down here at least you haven't

The 4%” barrel and barrel nut. Although similar in appearance, the barrel nut is slightly smaller than the one on the Uzi carbine.

screwed

up the gun. This assembly could even be

(legally) made before you file your Form

1 with

the BATF. The most logical order of converting is to first make all of the additional parts. Second — weld the additional piece to the leg of the striker and grind the camming surface on the bolt. We said grind, not mill! IMI cannot be faulted for not hardening

and heat treating their parts! With this work behind you, proceed with the balance of the modifications to the trigger housing and receiver.

SECONDARY The trigger housing stripped down and ready for modification. The magazine catch may be removed if desired.

SEAR CONSTRUCTION

The four parts of this assembly are welded into an inseparable unit and care must be exercised to

MICRO UZI MACHINE PISTOL insure proper fit and alignment. The pilot diameters on each end of the shaft should be a slight press fit into the trip lever and sear. After align-

ment, the end of the skaft can be staked to hold in place for welding on each end. After staking and

before

welding,

make

sure

the shaft is free to

rotate. It is a good idea to leave the cam surface of the trip lever a bit oversize. The lever can then be “fine

tuned” to trip the secondary sear when the bolt is approximately 1/8 inch from battery.

The stop block on the Uzi pistol has an offset to prevent the use of one of the available “full auto” selector levers.

Top view of the trigger housing showing the stop block that must be removed to allow the selector lever to move forward into the full auto position.

The selector lever slot must be filed 1/4” further to the front of the trigger housing (see drawing below).

-250

=

TOP VIEW, TRIGGER

HOUSING

(Remove Shaded Area) Scale:

1:1

10

REMOVE BLOCK BY MILLING

MICRO

UZI MACHINE PISTOL

The finishing touch to the trigger housing is to overstamp the F into an R and to stamp an A in the full auto position. After stamping, the letters can be filled with enamel to look “factory original’’.

The same stamping jig as described in Firepower Publications Book No. FP-4, “SELECT

FIRE UZI", can be used on the Uzi pistol housing.

11

MICRO UZI MACHINE PISTOL

1.00 ——_——_}>-

.156 DIA,

45° x .03 CHAMFER (FAR SIDE)

I 4 Tr

+ 175 R .450

a

.080 THICK 4130 STEEL *

2:1

-700 125 R

“i—

.156 DIA, 45° x .03 CHAMFER

500

150

A75R

.125 THICK 4130 STEEL

SECONDARY Scale:

2:1

12

SEAR

JS

TO BE “FINE TUNED”

AT FINAL ASSEMBLY

TRIP LEVER Scale:

THIS DIMENSION

MICRO UZI MACHINE PISTOL

——

.600

475

DRILL & TAP FOR 6-32 SCREW

(

\ |

.

to

-

|

»

by

a= i

.187 REAM

SCALE::2:1 MAT'L: Mild Steel

375

et —

0

.03 x 45° CHAMFER 2 PLACES

SECONDARY SEAR MOUNTING BLOCK

N

il I "i

>>

ir

970

4

MICRO UZ! MACHINE PISTOL

Scale:

2:1

+

>

- 187 DIA. *

1,185 REF

a

Y —>

—