Sten Mk II SMG Construction Manual 0879471972, 9780879471972

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a SMG | Se CONSTRUCTION MANUAL Cocking

handy

STEN MK IT SMG CONSTRUCTION MANUAL

WARNING !

The legal constructton and possession of « fully autonstic weapon is controlled by the Bureau of Alcohol, Tobacco, and Firearms diviston of the U.S. Treasury Oepartnent.

©1985 Minuteman Publications

Proper application to the @.A.7.f., authorization, and permission must be secured before constructing this or any other similar device. Local and state laws wary and may restrict ownership of this or similar type weapons. Severe ponalties are authorized for violators of these Taws. Minuteman Publications offers this Information for academic study of firearms design and disclaims any roma, or Wabitity for the improper or illegal use of this or other similar devices.

Printed

fn U.S.A,

MINUTEMAN PUBLICATIONS P.O. Box 695 Hurst, Texas 76053

1

BACKGROUND AND HISTORY OF THE STEN MKIT SMG

Table

Of Contents

CONTENTS

PAGE

Chapter1 Background And History Of The STEN MKIT SMG ..............2.22-., Chapter2 Reworking The STEN MKIT Parts Kit Chapter 3 Building The STEN MKII Receiver STEN MKIT RECEIVER TEMPLATE

The purpose ond scope of this Instructional manus] is to present a step-by-step procedure for building the STEN MK IT submachine gun, using for its foundation a commercially purchased STEN MK IT ports kit. The method presented in this text incorporates the use of « RECEIVER TEMPLATE which enables even the most inexperfenced builder to achieve professional results in constructing the STEN SMG.

2... .ccccescceucseecesees actos

5 Ot

The STEN MK £1 SMG 1s & Conventionnl type second generation submachine gun being chambered for the 9 mm cartridge. The origins of the STEN fe back to the early days of WWII, & time when Great Britain was desperately fighting far survivel. Great Britain had prion to that time tested various SMB designs, but had little real interest tn arnt its forces to any large degroo with this type weapon, American made 1928 THOMPSON .45 SMG‘s were

boing

imported

early

in

the

war

of

1939,

but

ft

was

an

expensfve

and complicated weapon to build, and a replacement was Sought. Another fmportant factor was that the German U-Boat campafgn tn the North Atlantic was having # devastating effect om allied shipping, many of the LEND-LEASE THOMPSON'S destinod for Britain resting in watery graves.

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.. 0.0... cc ccc cece e ees e eee eeenceeeceeee +

Chapter4 STEN MKIIT Recetver Assembly

...... 2.2.22 csc ee ceecesseecereeerecee

3D

Chap’ter 5 Final Assembly And Testing

> ..... 0.2.2.0. ccc sce ce ees cece eeeeeeeee

AF

The British evacuation of Dunkirk in June 1940 left the expeditionary force in a Gosperate situation since during the hasty retreat many of {ts weapons were lost to the Germans. The success of the Gennan MP-28 SMG was noted by the British, and a quickly destgqned Version incorporating many of the same features as the NP-26 was put {mto production. The new weapon was the LANCHESTER MKI, a reliable and robust weapon bearing 2 strong resemblance to the NP-28, At this pofmt the traditions] English quality wos still present. featuring volfshed blue stee?, a walmut stock, polished brass buttplate, and brass wagatiné housing. This weapon was still much too slow and expensive to produce considering the grovety of the situation, and work began designing a replacement for the LANCHESTER even before the first production models were completed. The following generation of British SWG's introduced a new concept in submachine gun design and manufacture, The STEN fomily evolved through the course of WWII, the basic design being developad by Reginald ¥. Shepperd, Director of the Birmingham Suet] Arms Company. and Harold J. Turpin, the principal designer fn conjunction with Royal Small Arms Factory at Enfield where the STEN was first produced. The name “STEM” 1s dertved from the first letter of the last name of each designer, and the first two letters of Enfield, Their first effort want from the drafting table

to actual production in less than three months. The resultant model was the STEN MK I, a selective fire versfon incorporating a spoon-bflled muzzle compensator, a folding front hand grip, complete barrel jacket with wing-protected front sight, wcod fore-end, and steel braced buttstock. Within a short time, the NK [ was replaced fn production with the STEN NK IL, reforred to by some as the “ugifest, nastiest weapon of the nar", The MK Il wes a simplifies version of the MK I, the darreal and barrel Jacket shortened, the muzzle compensator eliminated, 2 simplified buttstock known os the “T" stock design, and elimination of the sting swivels. However unrefined the MK II looked, {t performed as cesigned, and by the end of the NK f1 production run, aver two-milliog had been built, at a price of $5.20 per gun at the and of the run. Over 500,000 STEN MK II SNG's were supplied to varfous resistence groups by the end of the war, As subcontracters to B.S.A., the firms porducing the STEN components had previously manufactured @ wide variaty of products ranging froa hardwere, Jewelry, lawn mowers, and childrens scooters. The weapons were also extensively manufactured in Canada, Of great importance in producing & weapon of this type was the fact that complicated machine tooling was not noeded to produce the STEN guns. The basic design of the STEN was so functional that copies of it were built by Germany. China, Belgfun, Argentina, and Indonesia, Efforts to incresse production included other such novel approaches a5 casting the bolt of various metals including bress in an effort to Tininize machine work, and a barrel made of flat stock which had two rifling os milled into it, then wrapping the sheet oround a mandrel and welding the seam. The MK I] was jeter replaced by the STEN MK Ifl, a further offort to reduce cost and manufacturing time. The MK II] eliminated the removable barrel and jacket, fnstend using a formed and welded steel tudular receiver which housed the berrel and bolt mechanism, Tho NK III was the cheapest of the STEN family to produce, and all subsequent NK's were re-dosigned "i

retain

mage.

the

simplicity

of

the

weapon

but

improve

the

looks

and

general

Only about 2000 MK IV's were reported produced, boing an ultra compact unit designed for special purposes. A folding stock was used as well aS @ shortened barrel and pistol grip.

The STEK MK W was the last basic design of the STEN family, and was a baste ME IT with the addition of a wooden pistol-grip, = wooden stock, @ separate fore-end pistol grip, * muzzle desiqned to accept the No. 7 MK I and No. 4 MK IT bayonets, protective front sight wings, and sling swivels. The mota] finish was also much better than the earlier versions.

The STEN MK ¥ Stayed in service until the adoption of the STERLING*s in tho 1950's. A NK VI version was produced on a limited basis, being MK Y fitted with « shortomed vontilated barrel and Integral silencer, By 1945 more thon 4 million various MK's had been produced, and production virtually stopped except for spare parts, There has been a steady trade worldwide in STEN‘s since 1945, and these weapons can be expected to be found fm almost any area of the world. The expected life of the STEN SM3'S was set at one to two years in wortine use, the quality of fmeterials and workmanship being Somewhat compromised by the ¢fircusstances at that time. STEN

kits

from

de-militarized

Canadian

NK"s

show

better

worknsnship

im most cases, but in buying the tit tt wil) be virtually impossible to know the origin of the weapon, Some of the parts kits will exhibit heavy service, while others were never uncrated until the tine of their destruction. The STEM NK If 1s a very easy and controllable weapon to fire, and excellent results cam be achieved with this weapon. The best feature of all is the fact that the STEN MK If SMG can be owner-built for about $100,.00-$120.00, This puts this weapon fn a class that m guh enthusiasts can afford, the total cost for ownership after oayfing the $200.00 reqistration fee being approximately $320,00,

2 REWORKING THE STEN MKII PARTS KIT TECHNICAL DATA Cartridge: Opération: Fond: Front Sight: Rear Sight: Barrel: Rate Of Fire: Muzzle Velocity: Length:

6 groove, right hand 1 turn in 264mm {sono wil] §50 rounds per minute 1280 ft. per sec. Qverst] 30,0° 6.62 1d.

= 7.75*

being

AAMEX

(201)

647-3800.

453-0519;

barleycorn blade, drift adjustable Aperture, .120 diameter, non-adjustable

Barrel

Weight:

To build the STEM MK I! SMG it will first be necessary to acquire a parts kit which will contain a1] of the component parts except the com Pleted RECEIVER. Several sources of the STEN kits exist, two major ones

Sm X 19mm (Sim Parabet lum) blowback, selective fire 32-round box magezine

be 2-gro0ve}

and

INTERNATIONAL, SARCO,

INC.,

The parts

P.O. 323

BOX

UNION

252,

ST.,

SRODERICK,

STIRLING,

CA

NEW

95605,

JERSEY

(916)

07980,

kits supplied by both of these firms sell

for

under $100.00, and are comprised of parts removed Fron "de-mil{tarized* guns. In de-mtlling « STEN for export to the U.S., the RECEIVER fs destroyed by sewing the tubing section off of the BARREL BUSHING, TRIGGER HOUSING, and REAR RECELVER BUSHING, After removing the tubing the weapon is then classified 43 @ “non-gun” ond is legal for importetion into this country. When the parts kit is received, check to se# If all of the components have been fncluded. A Vist is provided at the end of this this would be 4 Slower process, but excellent results can be achteved in th{s manner,

The key coraponent of tie STEN MK I SMG ts the recetver, which can easil: ly and accurately be tuitt without complex layouts by the builder, This manuel inches the “STEN MK 0 Recotwr Te mplote' n ’ a full atzo template which ia removed from the manual and banded to the outer surface of the recetver tube, An «. xcellent adhesive for this purpose is 3M brand PHOTO-MOUNT, @ commercial aprey adhesive ovellable from most photo shops, Simply spray the back of the

the template js "square", The adhesive which wos used In this Project wes PHOTO MOUNT by 34. This {3 4m aerosol which is sprayed directly onto the beck of the temlate. This method js very ecesy and mess free.

After bonding the STEN MK I] Receiver Template to the receiver tubing, the buikier hap only ta cut out the shaded areas, This technique eliminates alfficult iayouts and the risk of error. Bottom view of recetver detailing triggen/sear opening ti center of tube. Note on right side for the barrel siseve fotch pin. The ejeetion port fupper front), magazine opening {lower frant) can be seen in this view,

sint and

This is how the receiver will look after cutting out the shoded areas and removing the template, Use a solvent wuch os acetone or alcohol to remove the template adhesive. his view shows the receiver inverted, left-und side, with the opening for tie trigger and sear located fn the top canter ares, Note slot next to magazine opening for barret sloove latoh pit. See alc locking slots on far left side for the Return Spring

Cop.

Right hand view of completed receiver. Note the cocking hendie slot and safety notch for rotating the bolt into when cerrying cocked In "sofe" condition, Also note large ejection port in front right hore side of the recetver.

26

Close up detail of the right rear zection of the receiver tube, showing one of the patr of locking notches in whic? He retum spring cop lugs enpape to hold return spring ond return spring housing, The cap has @ center hole fitting over the protruding "button" of the retum spring housing. This assembly (s inserted into the slots, rotated to the right, and released which allows the cep to move into ¢ locked position under tension from the retum spring,

The various areas

1.

removed on the template

represent

fron left to right:

RETURN SPRING CAP aes NOTCHES ~ Two sets of notches are cut into the rear of ¢ opposed to cach other, It is into these Slots that the two “ears of the RETURN SPRING CAP will locate when assembled. The slots are machined in 2 "J" shaped configuration, and the RETURN SPRING CAP js inserted, rotated untf] ft stops, and thon ?s reteased which, being under rearward pressure from the RETURN SPRING, Tocks the CAP and prevents movement, Dissassembly is perforned by reversing the assembly procedure. COCKING HANDLE AND SAFETY NOTCH SLOTS - The BOLT HANDLE is assembled to ft + anc rociprocates back and forth in tha slot in the right side of the recetver. The STEN MK [1] also features a safety notch in which the BOLT HANDLE {1 positioned when carrying the weopon in a loaded manner.

3,

SEAR LEVER AND SEAR Nace OPENING - The botton of the RECEIVER is relieved to acconodate tl on the right side of the opening, and the SEAR LEVER, which extends up into the receiver, on the lower left side, Both of these parts make contact with the BOLT; the SEAR which folds the BOLT ASSEMBLY open im tho cocked position, and the aa whe which moves laterally according to the position of the LEC EJECTION PORT ~ The large rectangular opening at the top of the template represents the ejection port which fs Tocoted on the right side of the finished recetver. MAGAZINE OPENING - The rectongular opening at the lower portion of the template 49 the magazine opening, the point in which the magazine protrudes into the receiver when inserted into the MAGAZINE HOUSING.

6.

MAGAZINE HOUSING A TGHNENT SLOT = The vertical slot located at the fa of the tonplate 1s the slot fnto which the spring-tensioned BARREL SLEEWE LATCH PIN locates In assembly. After the BARREL BUSHING fs ettached to the RECEIVER, this slot becomes a shallow “quide” 058 deep into which the pin locates. The slot is made long enough that the MAGAZINE HOUSING may rotate 90°, fron a firing position horizontally to a vartical position ff which the magazine opening and ejection part are closed, preventing contamination from dirt or other trash. tis proved fo be useful in WAIl, especially tn the dusty campaigns of the North African desert. When carried in this position, the user merely rotates the MAGAZINE HOUSING up until #% Tocks, the weapon then operational.

Ts

BARREL SLEEVE LATCH POLE - When rototing the MAGAZINE HOUSING upward as descrided tn shove, the travel of the assembly fe limited by the length of the slot, which will stop the MAGAZINE HOUSING at a point horizontal to the weapon, and fm which the magazine well fs

~ STEN MKT

SMG RECEIVER TEMPLATE

TO USE, REMOVE TEMPLATE FROM MANUAL AND CUT OUT AROUND OUTSIDE BORDERL INES.

WII

ss STEN

\

MK II

SMG

\

\ N

Receiver Template

©1984 MINUTEMAN PUBLICATIONS oss

Tem

*

OFF

temecATe MAKING

'F A

(E\THER

THE wn

THIS Are

LEGAL

END On

OF You

‘

Fitenem.

DEPEMDIG KIT) 3

lined up with the magazine opening, At this point, « BARREL SLEEVE LATCH positioned on the GARREL SLEEVE LATCH PIN will onter a hole extending oe the RECEIVER and BARREL BUSHING, then engaging and locking the BARREL SLEEVE tn place, The latch has grooved teeth which grip machined ricges on the outer diameter of the BARSEL SLEEVE. The purpose of this engagenent is to prevent the BARREL SLEEVE and SAMREL From vibrating loose during firing,

8.

EJECTOR SLOT - The reworked efector will be positioned in the stot The ejector is angular in shape, the adjacent the magazine opening. Attachment ts by welding. raised portion facing forward.

After completing all of the described operations completely deburr al] sharp edges, paying particular instde diamoter since any burrs moy prevant operation of the renoining template with @ suitable solvent, and the ready for assembly with the TRIGGER MQUSING-REAR RECEIVER BARREL BUSHING, MAGAZINE HOUSING, and FRONT SIGHT,

to the RECEIVER, attention to the the BOLT. Renove RECEIVER is now BUSHING, EJECTOR,

Close up detail of rear of the receiver tube, showing the slota for attachment of the retum spring cap, These alota were machined with a mill and then hand filed to make the coriers square, An gitemate method of building the recetyer without the use ofa milling machine ts to hand arit? os much of the metai out first, and then

use a hand

grinder

such

finishing with hand files. The ,058 walled tubing.

as a OREMEL

MOTO-TOOL

to finish rugh

stock

removal,

This method && easy, and progresses zurprisingly fant with

33

sli

VIEW

.800

400

+ —2300—+F+ 100 B

. 8 on

tN ae b$=. e

|

;

+

\

|

Cc

(S50 —— 550 —

95), ee +/00 >

-

12.400

*

FRONT

DETAIL - “A” “B" “C" "J"

=

— -

TRIGGER/SEAR OPENING EJECTION PORT MAGAZINE OPENING SLOT, BARREL SLEEVE LATCH PIN

Pee

ee

Hie

&—

C

ie

Vos

Ye

=" .250

=

ee

"A" - EJECTION PORT "RB" - MAGAZINE OPENING "C” - EJECTOR SLOT

—»| }—

G—

.200

1.000

LEFT SIDE VIEW

=

REAR

¢ RIGHT SIDE

\

BOLT HANDLE SLOT

¥,

a

“|

45° ROTATED

,

—

:

EGO:

=o ——" 7 ko 6.150

r#— | 465

RETURN SPRING CAP LOCKING LUG SLOTS

PrEGRT RIGHT

SIDE

LEFT

SIDE

Le.

ce

s

e

Xo,

BOTTOM

250 WIDE SLOT TYPICAL 4 PLACES

e—

200

4t—

400

t—

600

In normal use the weapon is never dissausembied further

STEN MKIT RECEIVER ASSEMBLY

After

conpleting

construction

of

the

RECEIVER

tube

and

reworking

D - Bolt Assembly (Breech-Block)

A - Magazine, 32 rd.

C = Recelver Assembly, complete

B ~ Barrel arei Barre! Sleeve

& - Bolt Handle (Cocking Handle} F - Retur Soaring, Retin Spring Housing, and Return Spring Cap G - Skeleton Stock

all of the de-milled parts as outlined tn the previous chapters, it is then time to assemble the components and weld thete to the RECEIVER. Welding techniques commonly used for this type of assembly include arc welding, ges welding, and holf-arc welding. All of these are suitable, with the builders ability and/or avatlability dfctating which tyge is chosen, Heli-arc.was chosen for thit project because of its meatness and good controllability, Anothor essembly method which may be used under improvised conditions #s brazing and silver-soldering. These can provide good strength if properly cone and can be quite durable.

into tts principle assemblies, field stripped ff) SMG STEN MK than this,

NVA

4

Insert the BARREL BUSHING into the front of the RECEIVER moking sure that the two holes drilled through the Sushing align with the barrel sleeve Jatch hole and barre] Sleeve fatch pin slot In the RECEIVER. At this time, tack weld the busting and tube togethor where the two parts cone together. If the tube previously has been drilled with filler-weld holes, these can be welded at this time. Be sure to balamce the heat so that the tubing wall 14s not erroded away. Use a mild steel filler rod ff gas or heli-arc welding, working the puddle until the hole is full and stightty higher than tho surrounding tube, A good filler material 7s comion clothes hanger wire. It ts advisable to cool ‘the tubing end bushing between each weld to prevent warpage of the RECEIVER The TRIGGER HOUSING and REAR RECEEVER BUSHING are next positioned onto the rear of the RECEIVER, alfgning the star and sear lover opening with the inside of the TRIGGER HOUSING. The TRIGGER HOUSING should be eligned perpendicalarly with the magezine opening ond ejection port. Nake sure that the rear of the tuding 1s flush with the rear of the TRIGGER HOUSING

' .

and

lower

edge

of

the

REAR

RECEIVER

BUSHING.

Tack

weld

the

parts

in position and recheck alignment. If still in position weld the two tabs to the RECEIVER, again taking care not to overheat the tubing. fNext vole the area at the top of the bushing directly fn front of the rear sight. A one-half inch long weld st this point will be sufficient. The point at the lower edge of the RECEIVER tubing where it fits flush against the REAR RECEIVER BUSHING can now have a short weld where the two cane together, This weld only needs to be about .250 - .400 long. The TRIGGER wn ag REAR RECEIVER BUSHING will mow be sacurely fastened to the VER,

The only remaining task tn completing the recefver construction is the attachment of the EJECTOR. The corresponding slot in the RECEIVER for the EJECTOR will be loceted adjoining the mayazine opening. The EJECTOR fs to be positioned so that the lower front edge of it will be flush with the rear edge of the magazine opening, In this position, the top contact ares of the EJECTOR will extend forward into the magazine opening and will overlap into the relfeved area of @ loaded magazine when inserted and latched into the MAGAZINE HOUSING. Note the de-nilled EJECTOR as ft 15. Supplied fn the parts kit, and this relationship can be noted. The EJECTOR gan be welded im place from the outside, building the weld up slightly end then filing it down and smoothing the surface later.

The barrel bushing slides inte the front of the receiver, aligning the hotes tn the bushing with the notched hole and slot in the recefver. The Qushing fs then welded to the receiver, either at the pomt where they come together at the front of the tubs, or by having three eventy spaced 1/8" diameter drilled holes drilled through the tubing (nto whith filler rod is welded to the bushing and receiver. The welds ore then smoothed down fo the 0.D, of the receiver,

After having performed the aforementioned assembly and welding operations, the dovetail slat for tha FRONT SIGHT Should now be cut. This is to be located forward of the MAGAZINE HOUSING, on top of the RECEIVER tube. Heving previously noted the position of the slot in the un-modifted BARREL BUSHING, simply cut the new slot at the same point on the new ossembly. The reason that ¢ dimension is not given fs because of variations in the location of this slot im the parts tits. [t is much easier if the slot fs cut to match the BARREL BUSHING supplied. This slot may be machined using @ dovetef] cutter available especially for this purpose, or tt may also be filed by hand to fit the sight. The fino) fit should be such that the sight fits tight enough that it has to be “drifted” into position using a mallet and brass punch. Actual field testing wil) deterRine the final position and “zero”. It may be noted that the WHIT STEN's had the FRONT SIGHT welded in place, witch prevented any adjustment of the point of impact, The weapons are factory set, and any correction required removing the weld first. By having the sight welded in place the MAGAZINE HOUSING cannot be removed from the RECEIVER, sfnce it assembles from the front. The weapon built for this manual does not have the FRONT SIGHT welded in place since ft 1s necessary to strip down for instructional purposes, but the individual builder may choose to do this on his om after establishing "zero". In all realfty there is mo reason to renove the sight and magazine housing after final assenbly. This completes the assembly of the RECEIVER, BARREL BUSHING, and TRIGGER HOUSING - REAR RECEIVER BUSHING, Al] welds can be drossed down with @ flat smooth file, and lightly sanded to remove filing marks. At this point al? parts of the weapon including the newly manufactured RECEIYER con be refinished to the bdullders personal preference. The ortginal Finish used in WWII wos a heavy black or gray enamel paint which, although valy and scratch prono, worked well and was easy to apply. Alternative fintshes {nclude porkertzing and traditional Sluing. Parkerizing 1s the most durable finish, with the process being sinilar to bluing. Vartations in the color range from gray, black, and dark green-gray,

Detail of completed

borre!

bushing assembly

into recetver,

ox viewed

from

left side.

Note front hole passing through both bushing ard receiver, for claw of borret steeve Igteh. in tre

Also note rear hole through receiver wall a shown here

and limit its rotation to 90°

bushing for barrel sleeve Intch pin, The 90* slot acte as a guide to posttton the magazine housing

4l

5 FINAL ASSENBLY AND TESTING

Before assembling the entire weapon, the various sub-assemblies should be fndividually assembled. Each assembly wil] be described separstely, and then the final assembly will be described. Many of these asseeblies will be complete as recefved fn the parts kit. BARREL/BARREL SLEEVE - The barrel Sleove sifdes over the front of the barrel and locates against « flange at the rear of the barrel. Mote the cross drilled hole through the barrel about 2.0" from the breech. The RETAINING PIN is insarted through 2 rear cooling hole in the barre] sleeve, and is inserted into the hole im the barrel, Press the pin in firnly up to the head and, while reaching through the cooling hole opposite the pin head, bend the anns of the pin back against the barrel.

The trigger housing site tabs are wekied to the recetver, Vhe top of the rear recefver busting is weited Co the recetver, directly in front of the rear sight.

View

of

the

ejector

as

the right hand side through

seen

MAGAZINE HOUSING ASSEMBLY - The STEN MK II features @ rotating magozine housing, the purpose of which ts to provide some degree of protection to the weapon from outside contamination. The front of the magazine housing fas a guide bushing welded to ft, which has a hole drilled through it parallel to the magazino well, The BARREL SLEEVE LATCH PIN is inserted into the guide bushing, the GARREL SLEEVE LATCH PIN SPRING being positioned on the pin at this time. [t is mow necessary to compress the spring and install the BARREL SLEEVE LATCH, the pin passing through the latch, The latch should be positioned so that the locking "claw is pointing into the round opening of the magazine housing. The BARREL SLEEVE LATCH is flow secured im place by Inserting the cotter pin (COTTER PIN - BARREL SLEEVE LATCH PIX) through the latch pin im between the latch and magazine housing. Bend the two sides of the cotter pin back around the latch pin.

from

the ejection

port. The ejector ts positioned in a slot directly behind the magazine opening and is welded in ploce, The welt is then smoothed with the recetver 0.D..

down

BOLT ASSEMBLY = The holt {s also sometimes roforred to as a “breech-block” and features a fixed firing pin im the recessed face. Check the firing pin to deternine ff {t 15 excessively worn or broken. If ft fs damaged the bolt gust be replaced. Approximate protrusfon should be .040-.050. Insert the EXTRACTOR SPRING into the side of the bolt, then place the EXTRACTOR fn the slot over the spring. Using a punch or other suitable tool, compress the extractor and spring until the cross pin hole through the bolt body ond extractor are aligned. [nsert the EXTRACTOR PIN at this time, [t will fit slightly recessed in the hole on each