Contents Safety warnings Page 1. Safety warnings ......................................................... 3 2. Weapon theory......................................................... 11 2.1. Weapon description................................................. 11 2.2. Technical specifications........................................... 20 2.3 Accessories............................................................... 21 3. Handling ................................................................... 22 3.1.
Safety warnings Protect your eyes and ears Always wear adequate safety glasses and ear plugs or “earmuff” type protectors whenever you are shooting. Always make certain that persons close to you are similarly protected. Unprotected eyes may be injured by powder gas, carbon residue, lubricant, metallic particles or similar debris which may emanate occasionally from any firearm in normal use. Without ear protection, repeated exposure to shooting noise may lead to cumulative, permanent hearing loss.
Safety warnings All lubricants and aerosol spray lubricants in particular can penetrate cartridge primers and cause misfires. Some highly penetrative lubricants can also migrate inside cartridge cases and cause deterioration of the propellant powder; on firing, the powder may not ignite. If only the primer ignites, there is danger that the bullet may become lodged in the barrel. NEVER completely trust any safety 1 Your firearm comes equipped with an effective, welldesigned safety device.
Safety warnings Safety warnings 4 After every shooting practice, make a final check to be certain the firearm is unloaded before leaving the range. dent causing serious bodily injury or property damage may result. A firearm is a precision instrument and some replacement parts will require individual fitting to insure correct operation. Transport and storage Care and cleaning When transporting your firearm to and from shooting activities, keep it unloaded for your safety and for the safety of others.
Safety warnings recommended that any firearm sent to us for repair should be sent through a federally licensed dealer. 3 All firearms must be shipped to us prepaid. WE WILL NOT ACCEPT COLLECT SHIPMENTS. 4 Firearms returned for repair should be addressed to: SAN Swiss Arms AG, Industrieplatz, 8212 Neuhausen am Rheinfall, Switzerland. 5 Be sure to enclose a letter stating serial number, caliber and barrel length of your firearm. Also state nature of trouble experienced or work required.
Weapon theory Weapon theory SG 552 LB 3) long barrel version with diopter sight. 2.1.2. Barrel with receiver and gas system The rifle SG 552 can be used: distances of up to 300 m, semi automatic fire rapid semi automatic fire three-round bursts full auto operation The receiver guides the bolt and houses the locking system. The rear sight mount with diopter drum or integrated picatinny rail with flip up rear sight are also mounted on top of the receiver. illu.
Weapon theory Weapon theory 2.1.3. Bolt The bolt consists of two main parts: • Bolt head • Bolt carrier with gas piston Bolt head Bolt carrier with gas piston The bolt head locks the bolt assembly, houses the firing pin and the extractor and feeds the cartridges to the chamber. The bolt carrier guides the bolt head, controls the locking and unlocking by means of the cam, holds the gas piston and cocks the hammer.
Weapon theory Weapon theory 2.1.5. Trigger assembly and butt stock 1 2 3 The trigger assembly comprises all the parts required for firing a shot. The safety lever on both sides can be set to four positions: Position “S“: Position “1“: Position “3“: The weapon is locked in the safe position. The weapon will fire semi auto. The weapon fires 3-round burst. After each burst, the trigger must be released and then pulled again. Position “20“: The weapon fires in the full auto mode.
Weapon theory Weapon theory 2.1.6.2. Flip up sight mechanism Flip up rear sight (illu. 14) 2.1.7. Magazine The flip up sight mechanism comprise the rear and front flip up sight. The rear sight is made up of the: • Rear sight holder • Rear sight • Flat head screw 1 Rear sight holder 2 Rear sight 3 Flat head screw The magazine is transparent and has a capacity of 5,10,20 and 30 rounds.
Technical specifications Accessories 2.2. Technical specifications 2.3. Accessories SG 552 SG 552 LB mm/inches mm/inches 5,56 / .223 Rem 733 / 28.28 5,56 / .223 Rem 822 / 32.36 mm/inches 503 / 19.80 592 / 23.31 mm/inches 258 / 10.16 6 347 / 13.66 6 inches 7 7 Sights Type Sight base Range adjustment mm/inches m/yards flip up or 340 / 13.39 100 / 100 diopter sights 360 / 14.17 100 to 300 / 100 to 300 Weight Weapon incl.
Handling Handling 3. Handling 3.1. Important instructions • Before manipulating the weapon, make sure it is safe and that the trigger guard is put in vertical position. • Use only factory ammunition. • Use only ammunition that corresponds to the caliber of the weapon. • During all manipulations point the weapon in a safe direction. • Do not place your finger on the trigger until the target has been sighted. • Do not load the weapon until immediately before use.
Handling Handling 3.6. Filling and coupling of magazines 3.7. Aiming, firing and adjusting with diopter sight 3.6.1. Filling the magazine 3.6.2. Coupling of magazines 1. Place loading tool on magazine. 2. Insert the ammunition clip and press cartridges into magazine. 3. Remove loading tool. 1. Hold magazine vertically. 2. With the floorplate of the second or third magazine pointing to the rear, firstly connect the upper lugs, then rotate forward and connect lower lugs.
Handling Handling 3.7.2 Adjusting Elevation Windage To correct for elevation and windage, the corresponding correction screw is turned with a screwdriver. High shots are corrected by turning the elevation correction screw to the left. Low shots are corrected by turning the screw to the right. Shots to the right are corrected by turning the windage correction screw to the left. Shots to the left are corrected by turning the screw to the right. illu.
Handling Handling 3.8. Aiming, firing and adjusting with flip up sight To aim, align the eye, flip up rear sight, front sight and target. At all ranges, the fore sight should be aimed at the center of the target. Firing is therefore to the point of aim (illu. 29). Adjusting To correct the elevation, release the flat head screw of the flip up sight and shift the sight plate up or down respectively, then lock the flat head screw. Front sight (illu.
Handling Handling 3.10. Folding the butt stock 3.11. Firing with mittens or gloves 3.12. Rifle Grenades (Bullet trap type) Thumb in the butt stock catch and fold the butt stock so that it registers with the handguard under spring pressure. For firing with mittens or gloves the trigger guard can be pivoted to the left or right. For safety reasons the trigger guard must be placed in the vertical position before carrying out any manipulations. 3.12.1. General Butt stock folded (illu.
Handling Handling 3.13. Use of accessories 3.14. Field stripping 3.13.1. Carrying sling One end of the sling hooks into the lug on the foresight mount; the other end is attached to the butt stock. • To fix the taut sling, use the clip. • To maintain a taut sling, slip the clip over the sling strap. illu. 36) Sling hooked to foresight mount illu. 38) Sling attachment to the butt stock illu. 37) Sling hooked to rearsight mount illu. 39) Fix the taut sling 32 1.
Handling Handling 8. Twist bolt head out bolt carrier. 9. Pull lower handguard to rear and lift off. 10. Lift rear of upper handguard and extract it from front sight mount. 11. Press down the gas valve catch. Simultaneously twist and pull the gas valve to extract it. 12. Press down the gas valve catch. Rotate gas valve through 90° so that the headpiece notch faces the barrel. 13. Pull out the gas tube. 14.
Handling Handling 3.15. Assembly 15. Stripping the magazine: • Use the thick end of the firing pin to press in the retention lug of the floorplate. Slide out magazine floorplate to the rear. • Pull out floorplate catch together with magazine spring and follower. The weapon must always be assembled in the reverse order of stripping: 1. Assemble magazine. 2. Install firing pin: • Insert firing pin and spring into the bolt head. Ensure that notch is correctly located to accept retention stud.
Handling 5. 6. 7. 8. Install upper handguard. Install lower handguard. Assemble bolt Insert bolt: • Press on the firing pin to push the bolt head completely forward. • Insert bolt into the receiver housing, ensuring that the gas piston passes through the hole in the receiver housing. illu. 52) Insert bolt assembly 38 Handling 9. Insert cocking handle into its slot in the bolt carrier and check that the catch has registered. 11. Fitting trigger housing: 10.
Handling 3.16. Function check Each time the weapon is stripped, verify its functions as follows: Sequence of Procedure Handling d) Safety lever on "3”, pult the trigger and hold it back. • Hammer must drop. With hammer held back, cycle the action (allow bolt to slide forward slowly). • Hammer must drop immediately as the bolt locks up. 2. Remove magazine. Repeat the loading cycle. • On the third loading cycle, the hammer must not drop. 3. Inspect serial numbers. Release the trigger. 1.
Maintenance Maintenance 4. Maintenance 4.1.2. Cleaning after firing 4.1.3. Cleaning after malfunctioning 4.2. Cleaning and lubrication procedures 4.1. Types of maintenance Sequence of operations: 4.2.1. Prior to firing There are the following types of maintenance: • daily cleaning • cleaning after firing • cleaning after malfunctioning 1) Unload weapon 2) Field strip the weapon (see section 3.14.
Maintenance Function 4.2.3. Greasing and degreasing 4.2.5. Cleaning procedure 5. Function Sequence of operations: • Carry out stripping procedure. • Remove residual powder from the gas valve, gas tube and gas piston with weapon cleaning oil. • Clean the receiver and barrel from the rear. • Clean the trigger assembly and all remaining parts of the weapon. • Clean accessories. 5.1. General weapon function of SG 55X 1) Unload the weapon 2) Remove the bolt 3) Clean from the chamber down 4.2.4.
Function Function 5.1.3. Unlocking and recoil of bolt The gas pressure, generated by the burning powder, drives the bullet through the barrel (13). As soon as the projectile passes the gas port (15), propellant gas flows through the adjustable gas valve (14). The gas pressure acts on the gas piston (1) which pushes the bolt carrier (4) to the rear. During the rearward motion of the bolt carrier (4) the bolt head (5) is rotated by the control cam (3) so that the locking lugs (8) are disengaged.
Function In the final stage of the advance, the bolt head (5) locks up and the release bar (6) is depressed. The weapon is ready to be fired. Function 5.2. Trigger functions 5.2.2. Trigger in safe position "S” 5.2.3. Semiautomatic fire 5.2.1. General The safety lever (6) is set to "S”. The safety shaft (7) locks the trigger (8). The safety lever (6) is set to "1” and the hammer (3) is held by the trigger rod (4). illu. 64) Trigger in safe position "S” illu.
Function Function By pulling the trigger (8) and after having overcome the pressure point, the trigger rod (4) releases the hammer (3) which strikes the firing pin (9). The trigger rod (4) falls downwards. The recoiling bolt presses the hammer (3) down and releases the sear (5) via the release bar (2). The sear (5) catches the hammer (3). illu. 66) Striking the firing pin illu. 67) Trigger mechanism during bolt recoil 50 During the bolt advance, the bolt presses down the release bar (2).
Function When the hammer (3) is thrust forward, the chargeover (14) presses the pawl (13) via its eccentric (15) on the segment (10). The segment (10) jumps up by one notch. Function The advancing bolt presses the sear (5) via the release bar (2) to the rear thus releasing the hammer (3). The segment (10) moves up another notch. The recoiling bolt cocks the hammer (3) which is retained by the sear (5) (refer to illu. 67). illu.
Function Function 5.2.5. Full auto fire The safety lever (6) is set on "20”. The automatic fire pawl (11) which supports the trigger rod (4) lies in the groove of the safety shaft (7). By pulling the trigger (8) the trigger rod (4) is drawn to the rear and supported by the automatic fire pawl (11). The hammer (3) is released and strikes forward (refer to illu. 66). The recoiling bolt cocks the hammer (3) which is retained by the sear (5) (refer to illu. 67).
Appendix 6. Appendix 6.1.
Appendix 600 Butt 611 Butt stock 612 Butt catch 613 Butt catch spring 614 Clip 615 Spring pin 616 Butt plate 700 Magazine 711 Magazine casing 712 Magazine floorplate 713 Floorplate catch 714 Feeder 715 Magazine spring Appendix 6.2. Exploded drawing Information to be supplied when ordering spare parts: • • • • • Type of weapon Serial number Caliber Item number Parts designation Cannot be ordered as individual parts ** Only on SG 552 LB *** Only on SG 552 * illu.
Appendix illu.
SAN Swiss Arms AG Industrieplatz Postfach 1071 CH-8212 Neuhausen am Rheinfall Switzerland www.swissarms.ch Art. Nr. 34 931 920 Subject to change without notice.
