Description
The Timney AR-15 Competition trigger is a self-contained, single-stage drop-in module set to a fixed 4 lb pull. This 668-S is the small-pin, solid curved-shoe version. Timney sets the pull weight at the factory and it is not adjustable, so what you get is a clean break at 4 lbs with no creep and no tuning to do.
The cassette drops into any mil-spec small-pin AR-15 lower and rides on your rifle’s original hammer and trigger pins. Timney’s housing design keeps those pins from walking, so anti-walk pins are not required. The aluminum alloy housing carries a hammer wire-EDM cut from S7 tool steel and internals EDM cut from A2 tool steel heat treated to Rc 56-60. Every unit is hand-assembled and calibrated in Phoenix. In the box: the trigger module, set screws, and an Allen wrench.
Heads up: Timney says this AR-15 model does not fit .308 or 7.62 large-frame ARs or the S&W M&P 15-22. Large-frame rifles need the AR-10 Competition (670).
Specs
- Type: Single-stage, self-contained drop-in cassette
- Pull weight: 4 lb, factory set, non-adjustable
- Shoe: Solid curved
- Pin size: Small pin (mil-spec 0.154 in)
- Materials: Aluminum alloy housing, S7 tool steel hammer, A2 tool steel internals (Rc 56-60)
- Fits: Mil-spec AR-15 lowers in 5.56/.223; also the Grand Power Stribog per Timney
- Does not fit: AR-10 / .308 frames, S&W M&P 15-22
- Made in: USA, lifetime warranty
Who it’s for
Shooters who want a crisp drop-in trigger in a general-purpose or Tactical Games rifle and prefer a bit more weight under the finger than a 3 lb match trigger. Good pick for a duty-style or truck gun that still gets run on the clock.
Who should skip it
If the rifle is a dedicated 3-Gun or USPSA PCC-division gun, the 3 lb version (667-S) or the straight-shoe 667-S-ST breaks lighter for the same money. If you want to tune sear engagement and pull weight yourself, the Timney AR Calvin Elite (660CE) is adjustable and this one is not.




