Triggers Explained

More Than Just A Bang Switch

When it comes to the AR rifle platform, there’s no end to the number of “upgrades” and parts available for your rifle. One of the most important and often overlooked areas is the trigger (also known as the fire control group). While the trigger itself does not directly affect the accuracy of the rifle, it is one of the most crucial components where you, the shooter, interact with the rifle. As the rifle is only as accurate as the person holding it, the trigger can have a major impact on your groupings.

Simply replacing a trigger won’t make you or the rifle more accurate. But what it will do is offer the shooter consistency. When it comes to shot placement, a consistent trigger pull becomes more of a mental decision, rather than a mechanical one. For a rifle that only weighs a few pounds, accuracy is greatly affected by the mechanical forces the shooter is applying. By reducing these forces, an improved trigger is the single best way for a shooter to improve his shot placement.

The trigger movement and settings are what can make for a great trigger, or a terrible one. A trigger with a lot of creep and take-up will introduce a lot of movement before the trigger breaks. A lot of over-travel will introduce a lot of unnecessary movement in breaking the shot and resetting for the next trigger pull. This excess travel on each end of the trigger pull can take away from consistency because the rifle is seeing movement before, during and after the trigger release. A crisp, short trigger with a quick reset is ideal for most situations. 

Trigger pull weight can vary between applications and the shooter's preference. Most aftermarket triggers which will be used for range time and competition will have a pull weight between 3lbs-5lbs. For duty use, self-defense use and for the utmost reliability, a trigger weight of over 4.5lbs is preferred to prevent an accidental discharge and also to ensure that even hard NATO primers ignite. 

Now that we’ve established the importance of the trigger movements, let’s examine the variety of styles of triggers available. There are basically three categories of triggers:

• Mil-spec - The standard assembly that comes with 4 pieces. This assembly consists of the trigger itself, the hammer, the dis-connector, and two springs. As with everything mil-spec, some are pretty good and some are just crummy. Other than making the rifle go boom, there’s nothing special about these. There are a few tricks, such as reduced power springs (like the ones from JP Enterprises) that can make the mil-spec trigger feel much better by reducing the amount of pull required, but they don’t typically make it feel any “smoother”. The trigger pull weight of most mil-spec triggers is around 7lbs-10lbs.

• Improved Fire Control Groups - Very similar to the mil-spec design, there are quite a few triggers available on the market that are still comprised of the four pieces similar to a mil-spec trigger group, but are an improvement over a mil-spec unit. Each of the four components is custom made and installs the same way as a mil-spec trigger, but offer many advantages and options.

• LWRC's Enhanced Fire Control Group is an example of a very high quality trigger that is still using the standard Mil-Spec style parts, without any adjustments. For the highest reliability, not having any set screws or parts to come loose is a good attribute. 

• Some, like the JP EZ trigger, allow for adjustments to dial in all aspects of the trigger. Adjustments can be made to the trigger pull weight, creep, over travel and dis-connecter timing. The hammer is light weight, which helps reduce lock time and increase velocity. Lock time is the period of time it takes for hammer to trip and engage the firing pin completely. Another option is the JP Revolution Gear trigger, which has a circular trigger bow that rolls, helping to put your finger right where it needs to be.  Both JP EZ trigger options come with over-sized, anti-walk trigger pins. 

• Modular (Drop-In) – A modular trigger installs very differently than the previous two types. With a modular trigger, the entire fire control group is housed in one piece. They are typically easier to install than a 4 piece setup because all you have to do is drop it in and slide the pins through.              

**While almost all lower receivers use the same diameter pin for the trigger assembly (0.154”), please note that some manufacturers, primarily Colt, use a larger pin size (0.170”).

Single Stage vs Two Stage

When looking for a trigger, there are two different “actions” available. The selection of either is one of personal preference.

• Single Stage – A single stage trigger requires one range of motion to pull the trigger in order to release the hammer. The benefit of a single stage trigger is that it’s simple. Most shooters agree that a single stage trigger is crisper in the “break” of the trigger because you don't feel the initial resistance of the first stage. A majority of shooters prefer the single stage triggers for most applications. 
• Two Stage – A two stage trigger requires the shooter to pull the trigger until it hits a “break wall”, which is a stopping point between the first and second stages. Similar to taking up the slack as some people call it, the two stage trigger then breaks during the second stage after hitting the break wall. The benefit of a two stage trigger is that the shooter knows at exactly what point the trigger will break. A two stage trigger is usually preferred on a DMR or marksman style bench-rest rifle. 

Flat vs Curved

This particular option is straightforward. Some triggers have a traditional, curved bow, while others are flat. Some prefer the flat trigger because it offers more surface area for the finger pad to contact and a longer reach. The choice of flat vs curved is once again, a personal preference.

*Bolt catch releases that extend into the trigger guard, like the Phase 5 or BAD Lever, are rarely compatible with flat bow triggers. Some people don't mind them being close, but avoiding an accidental discharge should be the most important concern. 

Play With It

With such a wide variety of triggers available, there’s no right or wrong answer on which trigger is best for you, the shooter. Ultimately, get opinions from others on what they like and their preferences based on the shooting environment that matches yours. The best way to test them is with the trigger set in a lower receiver. We have many of these set up for our customers to pull on so the differences on each trigger can be felt. As always, the staff here at Strong-Side Tactical are always willing to help with finding the best trigger for your application. 

Anti-Rotation / Anti-Walk Trigger Pins

The mil-spec trigger pins on the AR15 platform are a known weak spot and failure point. These pins can break, wobble in place and even completely fall out of the receiver. If a trigger pin has a chance to rotate or wobble in the receiver, the holes in the receiver can wallow out, giving an inconsistent and possibly unsafe trigger. Many anti-walk pins are included with the trigger kits, as with CMC Triggers and the JP EZ triggers. These are both an upgrade to the standard trigger pins and prevent the pins from walking out of the receiver, but they still allow the trigger pins to rotate in place. If you want to get rid of trigger pin rotation, the pins from KNS Precision are a great way to solve this issue. Especially with registered/SBR lowers and pistol caliber carbine lowers, there is a lot of stress put on the trigger pins, not to mention an expensive lower receiver. These types of set ups would benefit greatly from a set of KNS pins. Any time you can prevent or postpone wear on an item, we recommend doing so. If you have a lower that has loose trigger pin holes or you want to have the tightest fit possible, KNS also offers the Oversized trigger pins that measure .1555".