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11.2. LET-OFF ADJUSTMENT

The information presented here is for educational purposes only. Please consult a professional gunsmith before and after conducting any work on a firearm...... In other words be smart about it, and use this info intelligently.


11.2.1. General


Only the armorer trained on the assault rifle is authorized to undertake let-off adjustments.

The let-off is correctly adjusted if the let-off cam of the sear lies upon the let-off spring arm and the sear notch is still only slightly engaged with the hammer notch.

During let-off adjustment, the hammer may not strike against the trigger housing.

The let-off is to be adjusted so that it is clearly felt with the winter trigger.

 

Seriefeuersperre, Winterabzug und Druckpunktvorriclitung

56 Anschlagstift
60 Seriefeuersperre
68 Winkelhebel mit Stift
69 Zwischenhebel
71 Federarm fOr Winterabzug
72 Druckpunktfederarrn
73 Druckpunktreguliermutter
75 Seriefeuerklinke
85 Winterabzug
92 Druckpunktnocken der Abzugstange
(Above Left) Trigger group, shown for clarity without sear and trigger. Part #60 is the white tab that signifies a semi-auto rifle. (Above) Diagram depicts actual safety positions.

 

11.2.2. Carrying Out the Adjustment


Sequence of Tasks!


1) Unload weapon!
2) Let-off inspection by the armorer
3) Remove trigger mechanism from the weapon
4) Inspection of trigger components (in detail, if necessary)
5) Mount clamping lever for let-off adjustment and clamp until the let-off adjustment nut protrudes from the hole in the trigger housing
6) With special socket wrench, turn the let-off adjustment nut as appropriate
7) Insert trigger mechanism (hammer cocked)
8) Re-inspect let-off on the assembled weapon
9) Carry out functional inspection accord
4 ng to paragraph 10.1.2.



Note:

Trouble
Remedy
Let-off drags, or the hammer cannot be released:
Tighten let-off adjustment nut
Let-off too weak or not present:
Loosen let-off adjustment nut



Figure 86
Adjusting the let-off





A. Correctly adjusted let-off

Figure 87
Correctly adjusted let-off


The let-off cam of the sear (b) presses against the let-off spring arm. The sear and hammer notches (a) are still only slightly engaged.


B. Unadjusted let-off

Figure 88
Let-off drags


The let-off cam of the sear (b) presses against the let-off spring arm. The sear and hammer notches (a) are too strongly engaged.

If the let-off adjustment nut is loosened all the way, the release pawl can no longer engage the sear (c).


Figure 89
Let-off too weak (or no let-off present)


The let-off cam of the sear presses against the let-off spring arm. The sear and hammer notches, however, are too slightly engaged (the let-off is too weak).

If the let-off adjustment nut is tightened all the way, the letoff cam of the sear does not reach the let-off spring arm (b). The sear notch releases the hammer (a) (no let-off is present).

 

 

Last Modified on March 17, 1999

aalbert@biggerhammer.net