Abstract: A trigger assembly group of the type used with a rifle stock replacement system is provided. The trigger assembly group and may include a trigger assembly, including a trigger coupled to a trigger rod, a locking plate coupled to the trigger rod and a preload cylinder coupled to the locking plate. This in combination with the firing elements of the existing rifle may comprise a firing control mechanism. The trigger assembly group may also include a trigger block with a recess adapted to receive the trigger rod and the locking plate. A safety spool may be a part of the trigger assembly group and include a cross hole, which may be adapted to receive the preload cylinder when the safety spool is in a first position and not receive the preload cylinder when the safety spool is in a second position.