The Geissele Super Dynamic Combat (SD-C) is a flat-bow two-stage trigger for AR-15 and M4 pattern rifles, fitting Mil-Spec lower receivers that use .154 in trigger and hammer pins.
The Geissele Super Dynamic Combat (SD-C, 05-165) pairs the proven SSA two-stage pull with Geissele's flat trigger bow. The flat shoe gives a consistent finger position and a mechanical advantage that makes the pull feel lighter and more controlled, while the distinct 90-degree break point sharpens your sense of exactly when the shot will fire.
Underneath, it is all SSA: smooth first-stage take-up, crisp second stage, full-power ignition springs and the safety margin that has made Geissele two-stages a common choice for hard-use rifles. If you have never run a flat bow, the SD-C is a straightforward introduction.
Key Features
- Flat trigger bow — consistent finger placement, improved leverage
- SSA two-stage pull — the proven Geissele architecture
- Distinct 90° break geometry — you know precisely when it fires
- Full-power ignition springs — dependable primer strikes
Compatibility & Fitment
Drop-in fit for AR-15/M4 pattern lower receivers with Mil-Spec .154 in trigger and hammer pins — the heavier, more forgiving two-stage weight suits a rifle used in gloves, in the cold and in the wet. Large-pin receivers are not compatible, so confirm your pin size before ordering. Installation is armorer-level work; run full function and safety checks after fitting.
Technical Specifications
Platform | AR-15 / M4 |
Fits | Mil-Spec lower receivers with .154 in trigger and hammer pins |
Type | Two-stage combat trigger, flat bow |
Made in | USA |
Brand | Geissele Automatics |
US Shipping & Support
Shipped from D&R Sports Center in the USA with fast, tracked delivery. Questions on fit, mounting or which model suits your setup? Our team is glad to help before and after your purchase.
Frequently Asked Questions
Which receivers will the SD-C fit?
It is a drop-in trigger for AR-15/M4 pattern lowers with mil-spec trigger pins. Large-pin receivers are not compatible, so check your pin holes before ordering. If you are unsure, measure them or contact us with the receiver make and model.
What kind of shooting is the SD-C intended for?
The C stands for combat: it is the two-stage Super Dynamic set up for service and general-purpose use, with a deliberate first stage and a defined wall rather than the lightest possible break. That makes it forgiving under stress and when wearing gloves. It still gives you the flat bow and the clean second stage that the Super Dynamic line is known for.
Why a flat bow rather than a curved trigger?
A flat shoe keeps the finger at a fixed distance from the pivot no matter where it contacts, so the perceived pull weight stays consistent. Shooters with larger hands or a lower finger placement often prefer it. If you want a lighter feel from the same flat-bow layout, the SD-E is the enhanced version of the same idea.
Do I need any extra parts?
It installs with standard trigger and hammer pins, so no additional hardware is required if yours are in good order. There is one configuration, so there is no variant to choose between.
