The Timney Competition 668S is a single-stage drop-in trigger for AR-15 and M4 pattern rifles, fitting small-pin (.154 in) lower receivers.
The classic Timney Competition — a hand-calibrated 4 lb single-stage trigger that has anchored match ARs for decades.
The Timney Competition 668S drops a glass-crisp 4 lb single-stage pull into small-pin (.154 in) AR-15 lowers. Each unit is hand-calibrated: no creep, minimal overtravel and a break so repeatable it becomes part of your subconscious — exactly what deliberate match shooting demands. The 4 lb weight is the time-proven balance point: light enough for precision, deliberate enough for stages shot under adrenaline.
This is the trigger that introduced generations of AR-15 shooters to what a clean break feels like, in a self-contained drop-in module that installs in minutes and holds its calibration for the life of the rifle.
How It Compares
Also compare the Timney Skeletonized 661S Single-Stage Trigger 3 lb for AR-15 Small Pin, Timney 667S-ST Single-Stage Trigger for AR-15 Small Pin and Timney 667S Single-Stage Trigger for AR-15 Small Pin. Browse all triggers and the full Timney Triggers range. New to this? Read our guide: AR-15 Trigger Buyer's Guide.
Ideal For
- Small-pin (.154 in) AR-15 and M4 lower receivers
- Match AR-15s that suit a hand-calibrated 4 lb single-stage break
- Shooters who want no creep and minimal overtravel
- A self-contained drop-in module that installs in minutes
Key Features
- Hand-calibrated 4 lb break — glass-crisp, zero creep
- Long match record — decades on competition lines
- Self-contained drop-in module — minutes to fit
- Small-pin (.154 in) fit — standard Mil-Spec lowers
Compatibility & Fitment
Drops into small-pin AR-15/M4 pattern lower receivers with .154 in trigger pins, using the existing pin holes. Large-pin receivers are not compatible, so confirm your pin size before ordering. Function-check the rifle fully before live fire.
Technical Specifications
Platform | AR-15 / M4 |
Fits | Small-pin (.154 in) AR-15 / M4 lower receivers |
Type | Single-stage trigger |
Finish | Black |
Pull Weight | 4 lb |
Made in | USA |
Brand | Timney Triggers |
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
What do I need to check for fitment on the 668S?
It is a drop-in trigger for AR-15/M4 pattern lower receivers built with small trigger pins, measuring .154 in. Large-pin receivers will not take it, so confirm your pin size before ordering rather than after. If you cannot tell from the receiver's paperwork, contact us with the make and model.
Who is a 4 lb single-stage trigger aimed at?
The 668S breaks in one clean stage at 4 lb, which is lighter and crisper than a standard trigger group but still substantial enough for general use rather than being a hair trigger. Single-stage suits shooters who want the break to come at a predictable point without a take-up stage to manage. It is finished in black and made in the USA.
How does it compare with Timney's lighter AR triggers?
Compared with the two-stage AR PRO, which uses an 8 oz first stage and 1.5 lb second stage, the 668S is a heavier, simpler pull with no wall to hold against. Many shooters find 4 lb a sensible compromise for a rifle that gets used in more than one discipline.
Is there anything else to buy alongside it?
No, the unit uses the pins already in your receiver and needs no additional hardware. Since it is a small-pin part, the only shopping decision is confirming your lower matches. Installation is ordinary trigger group replacement and should be followed by a careful function check.
