Single-Stage Precision (SSP) M4 Curved Bow

Last reviewed: 2026-04-18 by Jake Terry, FFL07/SOT3, with hands-on install experience on AR/AK/Glock platforms.

The Geissele Single-Stage Precision (SSP) M4 Curved Bow trigger is a true single-stage assembly engineered for AR15 and AR10 shooters who prioritize crisp break points over two-stage characteristics. Unlike hybrid or staged triggers that incorporate a take-up wall, the SSP begins engagement at rest position and breaks cleanly once contact pressure exceeds the preset threshold. This design eliminates slack, giving you immediate tactile feedback when the sear releases. For precision rifle work where trigger control dictates shot placement, the SSP delivers repeatable geometry across thousands of cycles.

The Mechanism

Geissele machines every SSP component from S7 tool steel, a shock-resistant alloy commonly used in punches, chisels, and industrial tooling. The material’s high toughness prevents stress fractures during repeated hammer strikes, while the black oxide surface treatment inhibits rust formation in humid or marine environments. Wire electrical discharge machining (EDM) cuts the sear and hammer profiles to tolerances measured in ten-thousandths of an inch, ensuring consistent engagement angles between individual units. The curved bow maintains the familiar feel of mil-spec triggers, reducing the learning curve when you transition from factory components.

Specs at a Glance

The SSP installs without gunsmithing—push both pins through the receiver lugs, seat the trigger assembly, and verify hammer function. Geissele designs the pin holes to mate with standard .154-inch receiver pockets, so you retain compatibility with anti-walk pin sets or standard mil-spec pins. Browse additional Geissele trigger options if you need two-stage characteristics or adjustable pull weights for different applications.

Who It’s For

Competitive precision rifle shooters benefit from the SSP’s elimination of take-up, which removes one variable during long-range engagements. The trigger breaks as soon as finger pressure exceeds the sear threshold, so you don’t telegraph movement through a creep phase. Hunters working from supported positions—bipod, sandbag, or prone—gain similar advantages when aligning crosshairs on vitals at extended distances. Three-gun competitors who prefer single-stage geometry over two-stage triggers find the short reset beneficial during rapid target transitions, though you should confirm your division rules permit aftermarket triggers before match day.

Installation Notes

Before installing the SSP, verify your lower receiver accepts mil-spec trigger groups. Receivers cut for proprietary trigger packs—Sig MPX, MCX, or certain pistol-caliber carbine variants—use different pin spacing or fire-control geometries and will not function correctly with this assembly. After seating the trigger, perform a function check: with the rifle unloaded and pointed in a safe direction, cock the hammer, apply trigger pressure until break, then maintain rearward pressure while manually pressing the hammer forward. Release the trigger slowly—you should hear and feel a distinct click as the disconnector resets. If the hammer follows the trigger forward without resetting, remove the assembly and inspect for debris or bent components before attempting live fire.