September 23, 2010
Timney's AR replacement trigger is far and away better than most stock units and allows for more precise bullet placement at the range and in the field.
My first home gunsmithing project was dumping a so-so trigger on a newly purchased Remington Model 700 and replacing it with a Timney aftermarket unit. I spent a whole day of digging ditches to pay for the thing, and boy was it worth the trouble. Not only did the new trigger cut the pull weight in half and completely eliminate creep, but I could also brag to the boys I had installed it myself without mentioning it only took a punch, a tack hammer, and about 5 minutes.
In the interim, I have continued down the home gunsmithing road and broken a gun or two. But my last project centered around an AR-15 lower with a poor trigger, two pins, a punch, and Timney's new Competition Model replacement trigger. I had the drop-in unit installed in 10 minutes. The new AR-15 replacement trigger is as perfect as was the Model 700 trigger I first installed 20 years ago.
Timney started building triggers in 1946 to replace the wretched, two-stage jobs found on the surplus Mausers, Springfields, and Enfields that made their way home from the battlefield into the hunting fields. The company's products required no filing or fitting and could be installed by a regular Joe who could field-strip a rifle and read instructions. The Timney folks also worked hard to make their products affordable, and the product line has since grown to more than 70 different triggers.
An Engineering Challenge
Three years ago Timney engineer Calvin Motley was on a prairie dog shoot testing some new bolt-action rifles. His guide asked about replacing the trigger in his favorite predator rifle, which happened to be an AR-15. But Timney had yet to dip its toes in the black-rifle market. After returning to his Phoenix, Arizona, shop, Motley set about designing a unit to fix his guide's problem.
"Because it was a semiauto, the trigger was harder to design--bolt guns are easier," Motley said. "It was a challenge to get it all in there and make it modular, like our other triggers."
A year later and after several revisions, Motley had a trigger that worked. The finished product has 11 parts set in a 6061-T6 anodized aluminum housing. Critical parts are machined using a wire electrical discharge machine that produces very precise, exact edges. The hammer, machined from a billet of S7 tool steel, is finished with a Teflon-nickel coating that prevents corrosion and increases lubricity. The trigger and disconnect are machined from A2 tool steel.
"Wire EDM equipment is very expensive but gives us a lot more precision," Motley said. "We end up with an accurate part that has sharp corners where we need sharp corners."
Drops Right In
Installing the unit is accomplished in a few steps. First, make sure your AR is unloaded. Then remove the pistol grip by unscrewing the hex-head bolt inside and put the safety detent and safety-detent spring captured by the pistol grip to the side. The safety should fall right out. Remove the stock trigger group by tapping out the hammer and trigger pins. The hammer, trigger, their captured springs, and disconnect should drop right out. Remember, they are spring loaded.
The unit drops right into the lower receiver and is held in place with existing trigger and hammer pins. Two additional setscrews are used to lock the housing setscrews in place. A small screwdriver can be used to pry the hammer spring legs up and away from the screw holes.
The Timney housing will drop down into the receiver, followed by the safety selector. Replace the hammer and trigger pins, being sure the housing is lined up with the receiver holes. While holding the hammer, pull the trigger and ease the hammer forward to allow you access to the two setscrews on each side of the housing underneath the hammer spring legs. These two screws should be tightened, and the two provided setscrews are used to lock them in place. Motley said to allow for tolerance stacking and the variances between receiver manufacturers; the housing's 1018 steel pin bushings are .005 inch larger than spec. The two setscrews push the housing/bushings against the pins to hold them in place. If your pins fall out, the setscrews are not properly tightened.
The final step is to install the grip, safety detent, and safety-detent spring. Don't bend the spring.
"Our biggest problem is that guys just don't read the instructions," Motley said. "We have a great installation slide show at www.timneytriggers.com. Read the instructions or watch the slide show before you start."
The trigger/hammer mechanical operation is basically the same as stock, though the parts look different. Creep and overtravel have been machined and engineered out of the replacement unit. The hammer strikes with slightly less force than a stock unit and is powered by music wire springs that hold their shape and strength better than stainless steel.
"We reduced the strike just a little to get a better trigger pull, but there have been few reliability issues reported by our customer-service people," Motley said. "We have a heavier hammer spring for the AR-10 units and a bigger hammer with more mass, so the units are not interchangeable."
Before shipping, triggers are placed in a fixture, checked for function, and the disconnect engagement and pull weight are set. The end user cannot adjust the pull weight but has a choice of 3 or 4 pounds. Two different models are available--a plane-Jane competition unit and one with a skeletonized trigger bow. The former retails for $194.95, and the latter costs $259.95.
My Lyman trigger pull gauge said there was only an extreme spread of 2 ounces over 10 pulls, while the average factory trigger will usually vary a pound or more. I thought the housing maintained an exact relationship between the parts and that was what produced the precise pulls. Motley explained otherwise:
"Precision parts and good surface finishes are what produce our smooth and consistent triggers," Motley said. "The housing keeps the parts assembled and makes installation easy, but it has very little to do once installed."
Maintenance is dirt simple, just blow out the housing with compressed air every so often--no lubrication is required. This easy-to-install, easy-to-maintain unit has proven its worth during accuracy-minded range sessions and prairie dog shoots. A crisp, precise, and repeatable trigger simply makes
you a better shot. While there are a lot of aftermarket triggers available, the Timney is the quickest and easiest unit I have used.