Sigarms Sig SG 550 SP, SG 551 SP Instructions Manual

							2.1.6 Sights mechanism 
 
The sights mechanism comprises the rear sight and foresight. 
 
The rear sight is 
made up of the: 
 
 

						

							 
 
Rear sight assembly 
 
1. Receiver casing 
2. Rear sight mount 
3. Elevation correction screw 
4. Rear sight drum 
5. Night sight 
6. Windage correction screw 
 
 
 
 
 
Front sight 
 
1. Front sight tunnel 
2. Front sight 
3. Night front sight 
4. Front sight screw 
 
 
 
 12  
						

							 
 
2.1.7. Magazine 
 
The magazine is transparent and has a capacity of twenty or thirty 
rounds. On either side of the casing there is a mechanism,  that allows 
several magazines to be connected if required. 
 
 
 
 
 
 
Magazine, dismantled 
 
1. Feeder 
2. Magazine spring 
3. Magazine floorplate catch 
4. Magazine floorplate 
5. Magazine coupling lugs 
6. Magazine casing 
 
 
 
 
 
 
 
 13  
						

							2.2. Technical specifications 
 
 
 
 
 
 
 
  SG 550 SG 551 
Dimensions  inches   
     
Caliber 
 
 inches .223        .223        
Total length  inches 39.29      34.53 
Length with butt folded  inches 30.39       25.63        
     
Barrel 
 
    
Barrel length  inches 20.78    16.02 (USA) 
14.3 (others)     
Number of grooves   6 6 
Rifling: 
SG550-1/ SG551-1 right inches 10 10 
SG550-2/ SG551-2 right inches 7 7 
     
Sights 
 
    
Type   Diopter sights 
Sight base  mm 21.26 18.34 
Range adjustment  m 100 to 400 
  yards 110 to 440 
     
Weight 
 
    
Weapon incl. empty 
magazine 
 lb 9.03         7.49 
Empty 20 rd. magazine  oz 3.35       
      
3.35              
           
Empty 30 rd. magazine  oz 3.87       
               
3.87           
Loaded 20 rd. magazine  oz 11.99     
      
11.99            
        
Loaded 30 rd. magazine  oz 16.75     
       
16.75            
 
 
 
 
Subject to change without notice 
 14  
						

							 
 
2.3. Accessories 
 
Every SIG assault rifle SG 500/551has the following accessories: 
 

						

							 
 
 
Cleaning kit 
 
1. Weapon grease tube 
2. Cleaning rod handle 
3. Grease brush 
4. Barrel brush 
5. Cleaning rod sections 
6. Extension rod with ferrule 
7. Cleaning jag 
8. Cleaning brush 
9. Simileather case 
10. Gas tube brush 
11. Chamber cleaning tool 
12. Barrel inspection mirror 
 
 
 
 16  
						

							3. Handling 
 
 
3.1 Important instructions 
 
 
 

						

							3.2. Loading the weapon 
 
1. Put the safety lever to position “S”; 
 
2. Swing the trigger guard into the vertical position; 
 
3. Insert the magazine and check that it is properly seated  by 
pressing forward; 
 
 
4. Carry out loading movement. (Pull the bolt handle fully back 
and let it fly forward) 
 
 
 
Inserting the magazine 
 
1. Safety lever 
2. Bolt 
3. Magazine 
4. Trigger guard 
 
 
 18  
						

							 
 
 
 
3.3. Unloading 
 
1. Put safety lever to position “S”; 
 
2. Swing trigger guard into vertical position; 
 
3. Remove magazine by pressing magazine catch; 
 
4. Carry out loading movement, with bolt retracted check for 
empty chamber; 
 
5. Switch safety lever to “1”, pull trigger (with weapon pointing 
downrange), switch safety lever to “S”. 
 
 
 
 
 
 
Check the chamber 
 
1. Chamber 
 
 
 
 19  
						

							3.4. Changing the magazine 
 
1. Put safety lever to position “S”; 
 
2. Swing trigger guard into vertical position; 
 
3. Remove magazine; 
 
4. Insert loaded magazine and check that it is properly seated  by 
pressing forward. 
 
 
 
3.5. Reloading 
 
1. Put safety lever to position “S”; 
 
2. Swing trigger guard into vertical position; 
 
3. Remove magazine; 
 
4. Insert loaded magazine and check that it is properly seated  
by pressing forward; 
 
5. Push the bolt catch up or pull back the bolt handle slightly and 
allow the bolt to fly forward. 
 
 
 
 
 
Push the bolt catch up 
 20