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 
 
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							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; 
 
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							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 
 
 
 
 
 
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							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 
 
 
 
 
 
 
 
 
 
 
 
 
 
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							15. Remove the firing pin: 
 

						

							16. Dismantle the magazine;  
 

						

							 
 
 
Figure 47 
 
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							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: