Introduction (frg. I) I. The Rifle, ·303 in., No.4, Mk. l(T) is a specially selected No.4, Mk. 1 rifle on which are incorporated certain modifications to convert it for sniping. Particulars of these are given below. 2. The selection of snipers' rifles is done during the testing of rifles after manufacture, when the weapons are being fired on testing ranges. The performance of individual rifles varies appreciably, and is finally assessed when a proving group is fired from each weapon under carefully standardised con- ditions. As many rifles. as are required for sniping are then selected from among those which have given the closest grouping, and are sent for conversion. 3. With 'each sniper's rifle is issued a Telescope, sighting, No. 32, Mk. 3, which is packed in a pressed steel box having a leather shoulder strap (jig. 2). The rifle and its boxed sighting telescope are packed in a wooden chest, S.A., No. 15, Mk. 1 (jig. 3). DESCRIPTION Rifle 4. The rifle is basically a No.4, Mk. 1 weapon, with the additions and alterations . detailed in th~ following paragraphs. 5. On the left-hand side of the rifle body, a drilled and threaded lug is secured by three screws immediately to the rear of the. gas escape hole, and a drilled pad is fitted over a threaded hole between the charger guide and the hinge point for the backsight (jig. 4). These locate the mounting' bracket of the sighting telescope, and accept the front and rear clamping screws respectively. 6. A wooden cheek pad is secured by two wood screws on the upper side of the butt stock immediately to the rear of the hand (jig. 1). This brings the firer's eye level with the line of sight through the telescope, and assists him in keeping the correct position of the eye backwards or forwards to suit the eye clearance, or eye relief, of the telescope. 7. To allow the telescope to be accommo- dated on the rifle with the line of sight at a convenient height above the centre-line of the bore, the battle aperture sight is not 'present on the tangent backsight. 8. There is an additiona:l sling swivel (Type T) which is secured on a screw at the forward end of the trigger guard, and the rifle is fitted with a leather sling which is sufficiently long to enable the firer, if it is preferable, to use the sling with its forward end on the lower band sling swivel and its rear end on the trigger guard sling swivel. The sling then becomes of the competition type, the point of attach- ment of the rear end of the sling to the rifle being nearest the firer's forward hand (jig. sq. Sight 9. The telescope, sighting, No. 32, Mk. 3 (jig. 6) is a terrestrial telescope giving a magnification of x3. The object glass is a cemented doublet at the plane of focus of which is positioned a sighting graticule con- sisting of a cross wire and a slender metal pointer (jig. 7). The image erecting system consists Qftwo cemented doublets, while the eyepiece is a symmetrical pair of cemented doublets (jig. 8). 10. The eye clearance, or eye relief, of the telescope is 2·5 in. This means that the Ramsden circle occurs 2·5 in. to the rear of the eyepiece, and the firer must plaee his eye in this position in order to see the full aiming picture and magnified field. , Fig. I. Rifle, ·303 ln., No.4, Mk. I(T) (Sniper's) RESTRICTED
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Introduction (frg. I)I. The Rifle, ·303 in., No.4, Mk. l(T) is aspecially selected No.4, Mk. 1 rifle on whichare incorporated certain modifications toconvert it for sniping. Particulars of theseare given below.
2. The selection of snipers' rifles is doneduring the testing of rifles after manufacture,when the weapons are being fired on testingranges. The performance of individual riflesvaries appreciably, and is finally assessedwhen a proving group is fired from eachweapon under carefully standardised con-ditions. As many rifles. as are required forsniping are then selected from among thosewhich have given the closest grouping, andare sent for conversion.
3. With 'each sniper's rifle is issued aTelescope, sighting, No. 32, Mk. 3, which ispacked in a pressed steel box having a leathershoulder strap (jig. 2). The rifle and its boxedsighting telescope are packed in a woodenchest, S.A., No. 15, Mk. 1 (jig. 3).
DESCRIPTIONRifle4. The rifle is basically a No.4, Mk. 1weapon, with the additions and alterations. detailed in th~ following paragraphs.
5. On the left-hand side of the rifle body, adrilled and threaded lug is secured by threescrews immediately to the rear of the. gasescape hole, and a drilled pad is fitted over athreaded hole between the charger guide andthe hinge point for the backsight (jig. 4).These locate the mounting' bracket of thesighting telescope, and accept the front andrear clamping screws respectively.
6. A wooden cheek pad is secured by twowood screws on the upper side of the butt
stock immediately to the rear of the hand(jig. 1). This brings the firer's eye level withthe line of sight through the telescope, andassists him in keeping the correct positionof the eye backwards or forwards to suit theeye clearance, or eye relief, of the telescope.
7. To allow the telescope to be accommo-dated on the rifle with the line of sight at aconvenient height above the centre-line ofthe bore, the battle aperture sight is not'present on the tangent backsight.
8. There is an additiona:l sling swivel (TypeT) which is secured on a screw at the forwardend of the trigger guard, and the rifle is fittedwith a leather sling which is sufficiently longto enable the firer, if it is preferable, to usethe sling with its forward end on the lowerband sling swivel and its rear end on the triggerguard sling swivel. The sling then becomesof the competition type, the point of attach-ment of the rear end of the sling to the riflebeing nearest the firer's forward hand (jig. sq.Sight9. The telescope, sighting, No. 32, Mk. 3(jig. 6) is a terrestrial telescope giving amagnification of x3. The object glass is acemented doublet at the plane of focus ofwhich is positioned a sighting graticule con-sisting of a cross wire and a slender metalpointer (jig. 7). The image erecting systemconsists Qftwo cemented doublets, while theeyepiece is a symmetrical pair of cementeddoublets (jig. 8).
10. The eye clearance, or eye relief, of thetelescope is 2·5 in. This means that theRamsden circle occurs 2·5 in. to the rear ofthe eyepiece, and the firer must plaee hiseye in this position in order to see the fullaiming picture and magnified field.
,Fig. I. Rifle, ·303 ln., No.4, Mk. I(T) (Sniper's)
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Th,s leaf issued with A.L. No. 32, September, 1952 A.P.I64IP, Vol. I, Sect. I, Chap. 13
II. Light transmission of a high order isobtained through the fact that all air-glasssurfaces are bloomed, including the exteriorsurfaces of the object glass and the eyepiece.
12. The telescope is waterproofed; that is,it is tested under compressed air and sealedin manufacture against the admission of theouter atmosphere, This prevents the conden-
Fig. 2. Telescope, sighting, No. 32, Mk. 3
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Fig. 3. Packing of rifle and sight
sation of moisture on the internal air-glasssurfaces of the lenses, but does not meanthatthe sight can be exposed to rain or heavymist without deterioration.
Leading particulars
13. The leading particulars of the sight areas follows:-MagnificationField of viewWorking diameter
0·25 in.2·5 in.AdjustedtoindividualrifleMovingwire, non-illuminated2·57 in.
Graticule
Focal length of O.G.
Identif!cati on14. The main nomenclature ofthe telescope is engraved on theupper side of the telescope tube.Below this, appear the manu-facturing data, thus:-
OS.2039A(Optical
Store partnumber)
CTS(Manu-turer's
monogram orinitials)
No. 19459(Manu-turingserial
number)"
1S. Each sight is collimated to its companionrifle, 'and must not be used with any otherweapon. For this reason, the serial numberof the rifle is stamped on the left-hand sideof the sight mounting bracket.
Fig. 4. Attachment points for sight
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This leof issued with A.t. No. 32, September, 1952 A.P.I64IP, Vol. I, Sect. I, Chop. 13
Fig. S. Adjustments t9 sling
16. To enable the clamping pieces to remainpaired with their cradle portions of themounting, each is stamped with its identity,and the same marking appears-on the matingcradle piece, on the right-hand side. Thismarking usually consists of a three-digitnumber.
lens surfaces are bloomed. If, for any reasonthe blooming is removed, the letter B iserased.
18. Also on the sight tube is the letter Win red oil paint, t in. high. This is put on thesight at the successfulconclusionof its water-proofing test. If any sight fails to pass thistest, the letter W does not appear. If thesight is satisfactory in all other respects, it
17. The letter B appears on the sight tubein blue oil paint, i in. high, to denote that the
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Fig. 6. Components of sight
may be issued for use in temperate climates.Waterproofed sights may be used in tropicalclimates without the risk of condensation onthe internal air-glass surfaces of the lenses.
numbered intervals of 100 yards and un-numbered intermediate markings of 50 yards.
20. The deflection drum, which is on theleft-hand side of the graticule housing, isgraduated to left and right of zero up to 16,in numbered intervals of 4 with un-numberedintermediate markings representing 2. Thesefigures denote minutes of angle of deflection,left or right.
Range and deflection adjustments19. The range setting required is obtainedby rotation of the range drum situated on theupper side of the graticule housing. The drumis graduated from zero to 1,000 yards with_.
-.......___
POINTER '""'-,PLATINOlD SILVER WIRE
·--.........~OOb DIA. I[z-, .~~. ,~'"\. ,gg
/.~~SSWIRE
PLATINOID SILVER.WIREr 0001 DIA. .>:
I . - J~',\ -If .....x. /
CONE·ENDED P,OINTER. i 'ANG~E OF CON'E-(l,OOA""o,, ,/
l --- .....-/ )'\ DIMENSIONS, __[' ARE IN INCHES"" ., /"--- - . '
A. CROSSWIRE DETAIL B. PICTURE PRESENTEDTO FIRER
Fig. 7. Sight graticule
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....
· • I
.;. m0GO
2F.
-- .rJ-~ .;._ _. .--' _. .._Q. ~- -.nX0 ~
..-!-- ~ -~
:I:.,J
Oa-\ I I Oa-Oa- DIMENSIONS ARE IN INCHES
- ":'0I
11·013
This leaf issued with A.L. No. 32, September, 1952
I 0,," I1·45
\
AP.14bl P, Vol. I, Sect. I, Chop. 13
CARE AND CLEANING
Fig. 8. Optical system
Rifle21. The screws securing the sight mountinglug and pad on the left-hand side of the bodyare locked by the centre-punching of metalinto one end of the screwdriver slot, and shouldnot work loose. If they do, however, theyshould be tightened.
22. The rifle should be cleaned and lubri-cated as detailed in Vol. 2, Sect. 1, Chap. 4.SightMounting the sight23. The correct way to mount the sight isto screw up both clamping screws together,and give the final tightening on the rearscrew.
Weather protection24. To protect the exterior surfaces of theobject glass and the eye-piece from deteriora-tion through the prolonged action of theatmosphere, the leather protector issued withthe sight is to be kept in position at all times,except when the telescope is actually in usefor sighting or observation.Transportati on25. Except when the rifle is required for im-mediate use, it must be earned with the sightdismounted and firmly clamped in its box.
Lens cleaning26. Issued with each telescope are twopieces of linen approximately six inchessquare. These are to be carefully used toclean the exterior surfaces of the object glassand the eyepiece. The linen must be abso-lutely dry. and free from dust or grit; it mustbe used sparingly, and only the minimum ofgentle rubbing must be given to removesmudges or condensation from the lenses.
Tightening of screws27. There are eight screws securing theupper portions of the clamping cradles, fourin each. These are locked by the centre-punching of metal into one end of eachscrewdriver slot; if any of the screws becomeloose they should be tightened but not other-wise disturbed. .
28. No other screws on the telescope are tobe touched, otherwise the optical system maybe put out of focus, necessitating a lengthyprocess of correction on an optical bench.Moreover, the waterproofed condition of thetelescope may by broken down by theadmission of moist atmosphere into thetelescope tube; condensation will then formon the interior surfaces of the lenses, and thesight rendered unserviceable ..
P21179 50224/G6087 1O/~2 4000 C & P Gp, 1RESTRICTED
