Construction
The design consists of a standalone module that would interact with existing fire control groups.
This unit functions by engaging or disengaging a spring which provides upward force on the back of the trigger bar. This cancels out part of the force of the prep spring resulting in a lighter trigger weight. The housing is constructed of 3D Printed ABS. In production volumes plastic injection molding or metal die casting would be used.
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Figure 3-1 Drop In Module Assembly CAD
The drop in module has four proprietary components: Module Housing, Transfer Bar, Selector Paddle, and Safety Selector. Additional COTS components consist of the following: Transfer Bar Spring, Selector Paddle Spring, Selector Paddle Pin, and Transfer Bar Pin.
Construction of the Module Housing and Selector Paddle are designed around a die cast or plastic injection molded component. For prototyping purposes functional assemblies may be made using additive manufacturing. The Transfer Bar is a bent sheet metal component.