SIG SAUER SWISS ARMS SG552 - Manual (Page 9)

2.1.6. Diopter Sights mechanism
The diopter sights mechanism comprise the rear sight
and foresight.
The rear sight is made up of the:
• Rear sight mount
• Diopter drum
• Windage correction screw
• Elevation correction screw
The diopter drum can be set to positions “1”, “2” and
“3”, corresponding to firing ranges 1OO m, 2OO m and
3OO m The positions marked in white correspond to
aiming point = point of impact.
Sighting position “1” is designed for immediate firing,
and two luminous dots are fitted laterally for aiming at
night.
The foresight with tunnel is fixed to its mount with the
foresight screw. A folding foresight is provided for use
at night with the night sights on the diopter drum.
Rearsight assembly (illu. 12)
1 Receiver casing
2 Rear sight mount
3 Elevation correction screw
4 Rear sight drum
5 Night sight
6 Windage correction screw
Front sight (illu. 13)
1 Front sight tunnel
2 Front sight
3 Night front sight
4 Front sight screw
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Weapon theory
2.1.5. Trigger assembly and butt stock
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“: The weapon is locked in the safe position.
Position “1“: The weapon will fire semi auto.
Position “3“: 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.
By pivoting the trigger guard to the right or left side the
trigger becomes accessible for shooting with mittens.
For safety reasons the trigger guard must not be shifted
until just before firing the weapon, and after firing it
should be immediately replaced in the normal position.
The folding butt stock is made of high strength synthetic
material. In the firing position it is held by the butt locking
mechanism, and when folded it is held by spring pressure
on the handguard.
Trigger assembly and butt stock from right (illu. 10)
1 Butt stock 4 Magazine catch
2 Safety lever 5 Trigger
3 Trigger casing 6 Pistol grip
Trigger assembly and butt from stock from left (illu. 11)
1 Trigger casing 5 Butt stock catch
2 Bolt catch 6 Pistol grip
3 Safety lever 7 Trigger guard
4 Butt stock 8 Magazine catch
Weapon theory
16
illu. 11) Trigger assembly and butt from stock from left illu. 12) Rear sight assembly illu. 13) Front sight
illu. 10) Trigger assembly and butt stock from right
1
1
2 3 4 5 6
2
3
4
1
1 2 3
4
2 3
4 5
6
8 7 5
6