The Arnold Jewell AR-15 Two Stage Trigger
It has been said that 90% of AR-15 accuracy comes from a quality upper, the remaining 10% from the lower. The trigger assembly is the single biggest factor in a rifle’s lower accuracy. A good trigger will not necessary make a good shooter however a good trigger will make a good shooter better.
Replacement triggers for the AR-15 come in two different major configurations: single and two stage. In a single stage trigger there is one constant pull until the point is reached where the rifle fires. In a two stage trigger there are two different trigger pulls as felt – the first stage of take up until a second firmer stage is felt beyond which the rifle fires. Most bolt-action hunting rifles have a single stage trigger while most military rifles have a two stage one.
I chose a Jewell Trigger to replace the plus 5-pound stock trigger in my Armalite M15A4 because I wanted to improve my scores on this target rifle. Even though the trigger has proven itself 100% reliable I would not recommend an after market trigger for a self defense rifle because of the extra frailty such parts add.
The Jewell Trigger is a two stage model that allows for the weight of both stages to be adjusted. I found installation to be just slightly more involved that stock trigger installation. There are three added parts to the Jewell Trigger along with a completely redesigned hammer and trigger. The extra parts are a pair of simple springs and a first stage adjustment plate. The first spring is used with the first stage adjustment plate to set the first stage pull. The adjustment plate looks like a spur gear with its teeth turned over to one side. The second additional spring is a retaining spring to keep the hammer and trigger pins in place.
The hammer, disconnect lever, and trigger are made from 440-C stainless steel and are heat treated to 57 to 59 rockwell C for long life according to the manufacture. The fit and finish are top notch. All special tools for installation and hex wrenches adjustment are included.
The trigger is adjustable for the amount of over travel using a hex wrench in a hex screw (see part 1 in the photograph). Second stage weight of pull is adjustable, again using a hex wrench (see part 2 in the photograph) These set screws have nylon inserts to ensure position retention after adjustment. To set the amount of first stage pull weight one of the included spring’s legs is moved into one of the adjustment plate’s teeth to increase or decrease the amount of first stage pull (see part 3 in the photograph). The included manual gives a step-by-step procedure, which is simple enough to follow. Adjustments are made by “shotgunning” the rifle open to expose the trigger, no further disassembly is needed.
The range of adjustment for the first stage pull is stated as from 1 pound up to 3 and a half pounds. The second stage range is from several ounces to 3 and a half pounds. Total pull weight is therefore from about 1 and a half pounds up to over 7 pounds. For competition the trigger can be simply set to the required minimum. In practice I found that my trigger adjusted down reliably to as low as just 12 ounces as measured by an RCBS trigger pull scale. The trigger pull is more of a trigger press at this low weight. I have found that my groups have shrunk noticeably over the stock trigger as there is less disturbance at the exact moment of the shot.
The Jewell Trigger has performed flawlessly at the range so far. The trigger is smooth as silk and gives the “breaking a glass rod” feel with each shot. There is no creep or roughness and if I had to summarize the feel in a single word it would be “sweet”. It’s clear to see why this premium trigger often has a waiting list of several months during peak demand periods.
Specifications for the Jewell Two-Stage Trigger: