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Beretta SubMachineGuns mod. PM12S

Instructions for use and routine maintenance

Contents

1…….DESCRIPTION AND FEATURES
- 1a….Identification
- 1b….Use
- 1c….Operation
- 1d….Main parts
- 1e….Devices
- 1f….Technical data
- 1g….Features
2……..HOW TO USE
3…….ROUTINE MAINTENANCE
- 3a….Field stripping
- 3b….Barrel-bolt cleaning
- 3c….Front sight adjustment
4…….DRAWINGS AND WEAPON PARTS
- 4a….Diagram showing all component parts

1 a....Identification

The Beretta Model 12 S, cal.9 mm. Parabellum Sub-machine Gun, is a «straight blowback» weapon with semi and full automatic fire capabilities.

....

Makers :
Fabbrica d'Armi P. Beretta S.p.A.
25063 Gardone Valtrompia (Brescia) – Italy
Type: Calibre 9 mm. Parabellum Sub-machine Gun
Model: 12 S
Material denomination: P.M. Cal. 9 Parabellum
Factory mark: P.B.


Weapon and recommended accessories:
PM 12S + Nr. 2 32/rds magazines
+ front sight regulator tool
+ normal, or 10 rd strip charging appliance
+ sling.

1 b....Use

The Beretta Model 12S Sub-Machine Gun, due to its simplicity of construction and operation, special safety provisions, limited weight and volume, is particularly suitable for use:
- in built-up populated areas and jungle combat conditions
- in armored and/or mechanized troops operations
- by special units
- in anti-riots and police operations.

- 1c….Operation

The 12 S Sub-machine Gun is an automatic «blowback» weapon which has both semiautomatic and full-automatic fire capabilities. Upon firing, the combustion of the powder inside the cartridge case develops, in the chamber, a pressure which fires the bullet and also propels the bolt backwards.
The barrel in the 12 S Sub-machine Gun is inserted within the bolt. This unique characteristic makes the weapon very compact and minimizes the upward movement of the muzzle during automatic firing.
The 12 S Sub-machine Gun fires in an -open bolt» position. In its forward movement, the bolt ejects the cartridge from the magazine into the chamber.
The fixed firing pin which protrudes from the bolt head, fires the bullet by striking the primer.
Once fired, the bolt moves backwards with the empty cartridge case engaged by the extractor hook.
On hitting against the fired ejector, the empty case is forced through the ejector opening.
.................. .

 

- 1d….Main parts

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

A Front cap catch - G Rear cap catch
B Front cap - H Rear cap
C Front sight - I Automatic safety
D Cocking handle - L Trigger
E Selector-safety - M Magazine latch
F Rear sight

- 1e….Devices

The 12 S Sub-machine Gun is provided with:
- closing device consisting of the telescopic bolt (blowback) and the recoil spring
- firing device consisting of: sear mechanism percussion mechanism
- extraction and ejection device consisting of: extractor (extractor hook) fixed ejector
- three-position selector-safety device: ordinary safety - semiautomatic fire - full automatic fire, controlled by a single lever. The ordinary safety immobilizes the automatic safety on the grip which, in turn, blocks the trigger
- the automatic safety device on the grip which blocks the trigger and prevents the opening of the bolt by means of the bolt stop tooth
- aiming device consisting of a two-position rear sight (up to 100 meters - up to 200 meters) and a front sight adjustable for elevation and windage
- folding stock.

- 1f….Technical data

Operation : Full automatic or semi-automatic: the weapon fires from an open bolt position.
System of operation : Blowback
Caliber : 9 mm. Parabellum
Ammunition 9 mm. : Parabellum NATO standard
Muzzle Velocity : (V0,5) 430 m/sec. approx.
Bullet Energy : (E0,5) 77 Kg/m. approx.
Cyclic rate of fire : 550/650 RPM
Length : (metal stock folded) 418 mm.
Length : (metal stock extended) 660 mm.
Barrel length : 200 mm.
Height : (without magazine) 180 mm.
Height : (with 32 round magazine) 244 mm.
Weight : (without magazine) 3.2 Kg. approx.
32 round magazine weight(empty) : 0.230 Kg. approx.
32 round magazine weight (full) : 0.570 Kg. approx.
Barrel rifling : 6 R.H. grooves - pitch mm. 250
Rear sight Two positions for: up to 100m. - up to 200 m.
Front sight : Adjustable for elevation and windage
Line of sight : length 285 mm.
Safety Ordinary : which blocks the trigger through the automatic safety.
Automatic : on the rear grip which immobilizes the trigger and blocks the bolt in a closed position.
Finish : With epoxy resins resistant to corrosion andwear. Black glossy plastic grips.


- 1g….Features

SELECTOR
The new selector allows for an extremely easy, precise and safe selection of three positions, namely: semi-automatic fire, full automatic fire and safety.

SIGHT
This new device (considerably strengthened) which has a higher degree of precision in aimed fire and greatly increased - accuracy, possesses the following advantages:
the possibility of regulating the aim for ranges at 100 and 200 meters by means of a simple 90" rotation of the rear sight mechanism;
- the possibility of regulating the aim both in elevation and windage by adjustment of the front sight only.

REAR CAP CATCH
The introduction of the new rear cap catch has the important advantages of:
- greater maneuverability of the rear, cap and the catch itself, for purposes of both stripping and assembling;
- the provision of a lock in position for the catch indicating the exact degree of tightening required for safety in the weapons' performance.
Should the rear cap not be completely screwed on and locked in position, the catch would remain raised, immediately indicating faulty tightening and at the same time interfering with the alignment of the sights.

FOLDING STOCK
The new folding stock has a much more robust and functional butt plate. It has two catches which firmly lock it in either an « open» or «closed» position, making it more practical and allowing for greater firing precision.

SEAR BLOCK
The new system permits the elimination of a possible «double shot» when the selector is in the semi-automatic firing position. This is due to the disengagement of the trigger-ratchet which is effected only by the regulated movement of the sear block joint which, in turn, can occur only once the bolt has been released.

EPOXY RESIN FINISH
The exterior surfaces of the weapon which might be particularly liable to corrosion are well protected (after phosphate treatment) with a light coating of epoxy resin. This treatment gives the surfaces the best protection possible from outside elements.

2……..HOW TO USE

Before use, check to see that the 12 S Sub-machine Gun is perfectly clean and lightly oiled.
The 12S Sub-machine Gun is used in the following way:

BOLT IN A CLOSED POSITION

1) Insert a full magazine.
2) Holding the weapon by its rear grip, pull the automatic safety. The manual (or ordinary) safety must not be turned on.
3) Pull back the bolt by means of the cocking handle until it remains open. The weapon is now ready to fire.
4) Always keeping the automatic safety pressed, pull the trigger. - lf the selector lever is in S position (semi-automatic), after having fired a shot the bolt remains in an open position.
5) Pull the trigger in order to fire again.
6) lf, however the selector lever is in R position (full automatic), the bolt automatically moves backwards and forwards and the weapon continues to fire as long as the trigger is kept pulled or the magazine contains rounds.

3……..Routine maintenance

- 3a….Field-stripping

Every time the weapon is used, or at least once a month, the cleaning of the 12S Sub-machine Gun's barrel and bolt is recommended. Proceed with its field-stripping in the following manner:

(BOLT IN A CLOSED POSITION)

- Extract the magazine.
- Pulling the front cap catch, unscrew the cap

- Remove the front cap, barrel, bolt group from the receiver.

- Separate the front cap from the barrel


and hence the barrel from the bolt.

- Pulling the rear cap catch upwards, unscrew the rear cap.

- Remove the recoil spring from the rear part of the receiver.

- In order to assemble, repeat the above steps in an inverse sequence.............. .......................................

 

- 3b….Barrel-bolt cleaning

Tools necessary for the cleaning of the 12 S Sub-machine Gun:
- 2-Piece cleaning rod
- Swabbing brush
- Flannel cloths
- Detergent and protective oil

BARREL CLEANING

- Assemble the cleaning rod
- Screw the swabbing brush onto it
- Immerse the brush in detergent oil and pass it a few times through the barrel
- Insert a piece of flannelette into the eye of the cleaning rod and pass it through the barrel
- Keep replacing the cloth with a new piece until it emerges from the barrel absolutely clean
- Slightly soak this last clean piece of flannelette in protective oil and pass it again through the barrel

BOLT CLEANING

- Clean the bolt with a cloth soaked in detergent oil after removing combustion residues deposited on the front part of the bolt and in the extractor housing
- Put a thin coat of oil on the bolt itself


- 3c….Front sight adjustment

The Beretta 12 S Sub-machine Gun is supplied with a front sight adjustable for elevation and windage. In order to do so use the recommended special tool.

ELEVATION
Should the weapon shoot high, rotate the front sight in an anticlockwise direction using the special tool.
Rotate it in a clockwise direction should the weapon shoot low.

WINDAGE
Using the same tool, unscrew the front sight strut bush nut and move it, with respect to the axis of the weapon:
- towards the right, if the weapon shoots to the right of the target
- towards the left, if the weapon shoots to the left of the target. Check the tightening of the front sight strut nut once adjustment has been made.

 

4……..DRAWINGS AND WEAPON PARTS
- 4a….Diagram showing all component parts


- 4a….Diagram showing all component parts

 
Parts Denominations
Cod.
 
 
Parts Denominations
Cod.
1
Front swivel snap ring . . . . . .
50009
43
Front handle . . . . . . . . .
52950
2
Front swivel . . . . . . . . .
53309
44
Front handle stay bolt nut . . . . .
52039
3
Front cap . . . . . . . . .
52669
45
Magazine box (32 rounds) . . . . .
56269
4
Barrel . . . . . . . . . .
51464
46
Magazine follower . . . . . . .
52141
5
Bolt . . . . . . . . . . .
78852
47
Magazine bottom . . . . . . .
52485
6
Extractor pin . . . . . . . . .
55108
48
Magazine spring and plate . . . . .
78833
7
Extractor . . . . . . . . . .
52284
49
Selector-safety spring guide . . . . .
92198
8
Extractor spring . . . . . . . .
53999
50
Selector-safety spring . . . . . .
90206
9
Front sight . . . . . . . . .
53716
51
Selector-safety . . . . . . . .
56183
10
Front sight strut bush nut . . . . .
52025
52
Selector-safety ring . . . . . . .
52686
11
Front sight strut bush
50753
53
Selector-safety snap ring . . . . .
97107
12
Receiver . . . . . . . . . .
76561
54
Rear handle bush spring
53761
13
Folding stock pin . . . . . . . .
92195
55
Rear handle bush . . . . . . .
50774
14
Folding stock catch . . . . . . .
52977
56
Grip screw (4 pieces) . . . . . .
57847
15
Folding stock catch pin . . . . . .
92172
57
Left grip . . . . . . . . . .
52696
16
Folding stock catch plunger . . . . .
92173
58
Rear handle . . . . . . . . .
77167
17
Folding stock catch plunger spring . . .
90170
59
Right grip . . . . . . . . .
52695
18
Folding stock articulation plunger spring
54524
60
Sear block articulation . . . . . .
56347
19
Folding stock articulation plunger .
55882
61
Sear block spring guide . . . . . .
92188
20
Folding stock . . . . . . . . .
76864
62
Sear block spring . . . . . . .
90193
21
Butt plate . . . . . . . . .
51120
63
Sear block body . . . . . . . .
51868
22
Butt plate pin snap ring
50016
64
Magazine latch . . . . . . . .
52638
23
Butt plate release button . . . . .
52608
65
Ejector . . . . . . . . . .
52189
24
Butt plate release button spring
90205
66
Ratchet spring . . . . . . . .
90215
25
Butt plate pin . . . . . . . .
54886
67
Sear block pin . . . . . . . .
54856
26
Rear sight pin snap ring (2 pieces) . . .
97030
68
Sear block limiting pin . . . . . .
55386
27
Rear sight pin . . . . . . . .
54885
69
Front cap catch . . . . . . . .
52958
28
Rear sight spring strut
92197
70
Front cap catch pin . . . . . . .
55207
29
Rear sight spring . . .
90213
71
Front cap catch spring . . . . . .
54101
30
Rear sight . . . . . . . . .
52027
72
Ejector pin . . . . . . . . .
56461
31
Rear cap catch . . . . . . . .
52980
73
Magazine latch spring . . . . . .
54034
32
Rear cap catch spring . . . . . .
53762
74
Ejector and magazine latch pin
56461
33
Rear cap catch spring pin . . . . .
92196
75
Trigger spring . . . . . . . .
53763
34
Recoil spring . . . . . . . .
54422
76
Trigger pin . . . . . . . . .
55386
35
Rear cap
52709
77
Ratchet pin . . . . . . . . .
92200
36
Rear swivel 
78665
78
Ratchet . . . . . . . . . .
54617
37
Shock absorber snap ring 
50016
79
Bolt stop tooth . . . . . . . .
76598
38
Shock absorber housing
52018
80
Automatic safety spring strut . . . .
78859
39
Shock absorber
50008
81
Automatic safety and trigger limiting pin .
55386
40
Recoil spring cap 
56180
82
Automatic safety . . . . . . .
78936
41
Front handle stay bolt pin
56641
83
Automatic safety limiting pin . . . .
56461
42
Front handle stay bolt . . . . . .
57112
84
Trigger . . . . . . . . . .
52705