Page 124 - FAT 105 4.17 MOODLE

One major drawback to the open bolt design is
Fire Control
its lack of accuracy and precision for the first
couple of rounds fired. With a closed bolt de-
sign, only the trigger, linkage and the hammer/ Group and Trigger
Operations
striker move right before the point of ignition.
This happens within milliseconds, which does
not permit much, if any, disruption from the
action or operator and allows the operator to Now that you have a basic understanding of the
hold the firearm more steadily during discharge. different firearm types and the actions that drive
With the open bolt design, the entire bolt/carri- them, you can dive a bit deeper into the “ignition”
er plus the fire control group all move. When the systems of these machines. There are two sys-
bolt slams forward, it creates a great disruption tems used and multiple ways these systems can
in the firearm, typically causing the first several function. These systems are not limited to one
rounds to be off of the intended target. The op- firearm or action type and can be found across
erator must then “walk” the rounds toward the the spectrum of firearms found across the world.
intended target by watching the impacts.
HAMMER- OR STRIKER-FIRED

There are two basic systems used to create ig-
nition in the cartridge’s primer: hammer and
striker. These two systems can be found in vari-
ous firearm types and in many different actions.
Both systems perform the same function, but in
very different ways.

Figure 2: A hammer-fired system.

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