Sigarms Sig SG 550 SP, SG 551 SP Instructions Manual

 
 
 
 
 
 
 
Sling hooked to rear sight mount 
 
Sling attachment to the butt 
 
 
 
 
 
Fix the taut sling 
 
 
 
 
3.13. Field stripping 
 
 31  

1. Unload weapon; 
 
2. Remove carrying sling; 
 
3. Press the rear trigger casing stud from both sides and withdraw 
it from the stud head side as far as the stop; 
 
4. Lay the weapon on its left side and swing out the trigger 
assembly; 
 
5. Withdraw the front trigger casing stud as described in point 3 
and remove the trigger assembly; 
 
 
 
 
 
 
Remove the trigger housing stud 
 
 
 
 
 
 
6. Press down the bolt handle catch and remove the bolt handle; 
 
 32  

7. Use the bolt handle to push the bolt to the rear, remove the 
bolt from the receiver; 
 
  
 
Remove the bolt handle 
 
Push the bolt to the rear, using bolt 
handle 
 
8. Twist the bolt head to remove it from the bolt carrier; 
 
  
 
Remove bolt head 
 
Remove bolt head 
 
 
 
 
 
 33  

9. Pull lower handguard to the rear and remove; swing out the 
bipod legs and remove laterally; 
 
10. Lift upper handguard at the rear and remove at the front sight 
mount; 
 
 
 
 
Lift off lower handguard 
 
 
 
 
 
Remove bipod carrier from the handguard 
 
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11. Press in the gas valve catch, remove the valve by 
simultaneously rotating it and pulling it forward; 
 
12. Push the Gas piston and recoil spring forward, reaching through 
the ejection port, and extract them from the front; 
 
13. Press down the gas-valve catch and rotate the gas tube through 
90o so that the notch on the headpiece lies on the barrel; 
 
14. Pull the gas tube out from the front end; 
 
 
 
 
 
 
 
 
 
 
Remove gas valve 
 
Push in gas piston 
 
 
 
 
 
 
 
 
 
 
 
 
 
 35  

15. Remove the firing pin: 
 

16. Dismantle the magazine;  
 

 
 
 
Figure 47 
 
 38  

SIG SG 550 dismantled 
3.14 Assembly 
 
The weapon should always be reassembled in the reverse order of 
stripping: 
 
1. Assemble magazine; 
 
2. Insert firing pin: 

3. Install the gas tube: