AR-15 Hacks: How to Maximize Your Rifle’s Accuracy Potential
Tom McHale 10.07.14
What if I told you that you could get 15, 20, or even 45 percent better accuracy from your existing AR-type rifle? You can. Read on.
The key concept here is getting the best possible accuracy from the rifle you already have. While you can certainly improve accuracy by replacing major components like the barrel, that kind of defeats the whole point of working with the rifle you have. Here, we’ll focus on less invasive upgrades.
There are a number of accessories available to shooters that can help improve accuracy. For example, on the AR platform, you can upgrade your front handguard to a free-floated design. Removing pressure points on the barrel will certainly help with shot-to-shot consistency (accuracy). Installing a free-floating handguard take a little bit of tool work, but can be well worthwhile in the long run.
Furniture aside, there’s another upgrade you can make that will positively impact the accuracy of your rifle. I’m talking about a trigger upgrade. AR factory triggers can be notoriously bad. Some are heavy, irregular, and feel like you’re trying to create sidewalk art with a broken piece of brick. The weird thing about trigger upgrades is that a new trigger doesn’t do anything to make your rifle mechanically more accurate—it doesn’t affect the bore, it doesn’t come into direct contact with the cartridges, and it doesn’t stabilize your shooting position. However, it does enable you to get the maximum possible accuracy out of your rifle.
Accurate shooting is a carefully-choreographed pas de deux between shooter and rifle. If you put your rifle in a vise and shoot, it will perform to a certain level of consistency from shot to shot. However, there is no shooting without a shooter. No matter how carefully you rest your gun, obtain your sight picture, and control your breathing, breaking a shot always requires physical force from you to press the trigger. This motion requires enough force to release the sear, drop the hammer and finally ignite the cartridge. Considering that standard AR triggers can require five to eight pounds of pressure to release, and that most rifles weigh six to eight pounds, there’s a great chance that the act of pressing the trigger will exert some unwanted movement on the gun. The more irregular and grittier the trigger, the more risk of moving just a gnat’s hair from your perfect point of aim. Even the tiniest movement of a gun can affect group size downrange.
Recently, I did an experiment to quantify the effect of a trigger upgrade. To make a long story short, I shot a number of five-shot groups with standard triggers on two different rifles—a Daniel Defense DDM4v5 chambered in 300 BLK and a Rock River Arms LAR in 6.8mm Remington SPC. While still at the range, I removed the factory triggers and installed Timney AR-15 Competition triggers with three-pound pull weights. I re-shot the groups and compared average group sizes. Doing advanced math with a number of groups from two rifles, I observed between 15 and 40 percent improvements in 100-yard group size. To put those improvements in real terms, averages improved as follows:
- 300 BLK Sierra MatchKing 125-grain: 1.69 inches before, 0.970 inches after
- 300 BLK Sierra MatchKing 135-grain: 1.37 inches before, 1.007 inches after
- 6.8mm Remingt on SPC Sierra MatchKing 115-grain: 1.75 inches before, 1.47 inches after
Same shooter, same conditions, same ammo, same rifles—the only difference was the trigger.
Fortunately, replacing your trigger with a self-contained assembly like the Timney is a piece of cake. During my test, I did it on two different rifles on a range bench in the middle of the woods. Here’s how you do it.
First, you need to decide on a trigger replacement. Last week, I wrote about a factory tour of the Timney Triggers plant. I’m partial to Timney because their replacement trigger assembly is a complete unit—not a set of parts that you have to configure. Each trigger group has been assembled, adjusted, and tested before you ever see it. It’s a drop-in unit that replaces the trigger, hammer, and sear (and springs) of your existing AR trigger group. The following text will describe how to install a drop-in unit like Timney’s AR-15 Competition unit.
First, ensure your firearm is unloaded.
You’ll want to completely separate the upper and lower receivers, mainly because it’s easier to work on with the upper completely out of the way.
On the lower receiver, punch out the two pins that hold the trigger group components in place. This allows the three components of your factory-installed trigger group to be removed. Save them just in case you want to relive the experience of a crappy trigger at some future date.
Next, you’ll need to remove the pistol grip. The top right of the pistol grip holds the safety detent pin spring, so you need to take it off in order to release pressure on the safety detent pin to remove the safety. Be careful when removing the grip so you don’t lose the detent pin spring.
Once the detent spring is out, you’ll be able to remove the safety. You need to get the safety out of the way so the new trigger assembly will fit into the receiver.
Drop the new trigger group assembly into place. Once it’s fully seated, you’ll be able to reinsert the safety. Now you can reattach the pistol grip, taking care to make sure the safety detent pin and spring are in the correct place.
Now you can replace the two trigger group pins. By design, these will be loose in the Timney housing, so either hold them or tape them in place so you can complete the next step without the pins falling through.
Use the included Allen wrench to tight the two base screws in the trigger assembly housing. This applies pressure to the interior of the receiver so the trigger group pins are under tension. Two tiny set screws are included with the Timney trigger, along with an equally-tiny Allen wrench. Put those in place over the screws you just tightened to hold them in place.
Replace your upper receiver and test the function with your (still!) unloaded gun.
A couple of closing thoughts: be careful about the replacement trigger you choose. You want to match the purpose of the trigger to the anticipated use of your rifle. If you’re a target shooter, feel free to get a light trigger! If you intend to use your rifle for home defense, you might want to get a higher-weight replacement trigger to minimize the chance of negligent discharges while under stress. Luckily there are tons of aftermarket trigger options available, and you’ll likely be able to find one that meets your needs.
Tom McHale is the author of the Insanely Practical Guides book series that guides new and experienced shooters alike in a fun, approachable, and practical way. His books are available in print and eBook format on Amazon.