Page 83 - FAT 105 4.17 MOODLE

As the bolt continues to move rear- it to rotate into place in the groove in
ward and the lever pivots, the effort the receiver.
arm will move out of contact with
The lever delayed blowback system
the carrier. The momentum gener-
is capable of handling much higher
ated by the velocity of movement of
pressures than a standard blowback
the effort arm and the weight of the
operation. The lever delayed blowback
carrier will overcome the inertia of
action is most commonly associated
the action/recoil spring and continue
with the French MAS FAMAS F1
to drive the carrier rearward, pulling
and G2 rifles. These bullpup-style ri-
the bolt and cartridge case with it.
fles are chambered in 5.56x45 NATO
The bolt and carrier will now move
and were adopted by the French
rearward at the same speed. On its
military in 1978. The action has also
rearward travel, the bolt will extract
found use in many other firearms,
the case from the chamber and eject
including pistols, assault rifles, and
it and cock the hammer.
machine guns.
Once the bolt has reached the end of
› Gas delayed – The gas delayed blow-
its stroke and the action/recoil spring
back action is similar but different,
has almost fully compressed, the bolt
and should not be confused with the
will begin to be driven forward. On
gas-operated action. Unlike the gas-
its forward travel, the bolt will strip a
operated system, which uses a locking
round from the magazine, drive it into
chamber and tapped gasses to unlock
the chamber and seat it completely.
it, the gas delayed blowback system
The bolt will bottom out against the
uses those same gasses to delay the
barrel and cartridge and the carrier
chamber opening. Instead of the gas-
will continue forward, pushing against
ses acting against the bolt/slide trying
the effort arm of the lever and causing

Figure 7: Gas delayed blowback action.

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