Ar15 Assembly (Lower/ Trigger Group, Safety Selector & Grip)

Installing the Trigger Group

To install the trigger group you’ll need: your bench vise, the lower receiver vise block, a nylon/brass hammer, and a number 3 roll pin punch. This diameter punch will work for all the trigger and hammer pin sizes. If you’re installing an aftermarket or non-standard trigger group, be sure you read and understand the directions provided and test the trigger group according to the manufacturer’s recommendations.

• 1. Install the receiver onto the vise block and rotate it so you can clearly see down into the lower receiver.
• 2. Place the trigger spring under the trigger with the solid loop of the spring under the front of the

  

  trigger, and pull the loops over the trigger pin extensions.

• 3. Place the disconnector spring into the hole provided in the top of the trigger with the flared end of the disconnector spring first, followed by the disconnector. The hook of the disconnector should be facing forward and the hole in the disconnector should line up with the hole in the trigger.
• 4. Place the trigger with disconnector installed into the lower receiver. You’ll have to align the trigger pin with the trigger and disconnector holes to allow the trigger pin to pass all the way through. You can maintain alignment of the trigger and disconnector with your punch while you push in the trigger pin flush with the receiver.
• 5. Next, install the hammer spring onto the hammer. The closed loop will rest against the back of the hammer and pull the loops of the hammer spring over the hammer pivot points.
• 6. Place the hammer into the receiver with the tails of the hammer spring resting on top of trigger pin. Push the hammer down until the hammer pin holes align with the holes in the

  

  receiver. Use your punch to hold the hammer in place once you’ve aligned it.

• 7. Push the hammer pin in until it is secured by the J spring in the hammer. You may need to lightly tap the pin with the nylon tipped hammer to fully seat the pin into the receiver. Be sure the pin is properly aligned with the holes in the receiver.
• 8. We have to install the safety selector before we test the trigger. We’ll demonstrate the testing of the trigger in the next segment.

Safety Selector and Grip

To install the safety selector and pistol grip you’ll need a large flat head screw driver with a shaft at least 3 and half inches in length, and the lower receiver vise block.

• 1. Your hammer should be cocked in rear position. If it’s not, place your hand on the hammer and push it down while keeping your finger off of the trigger. Don’t allow the hammer to slam forward, it can damage the receiver.

  

• 2. Insert the safety selector into left side of the receiver with it pointing to the safe position.
• 3. Place your receiver upside down on the lower receiver vise block.
• 4. Now drop the detent in with the rounded tip facing in.
• 5. Install the selector spring into the hole in the pistol grip, retaining it with your finger, guide the spring into the passage for the safety detent while pushing the pistol grip onto the lower receiver.
• 6. Place the grip screw with the washer into the bottom of the grip.
• 7. Tighten the screw down to hold everything together.

  

• 8. Now that you have all of the components of the fire control system installed you can test them.
• 9. First we are going to confirm the function of the safety. With the hammer cocked back and the safety selector set to safe, put your thumb on top of the hammer to control it if it releases. Pull the trigger. The hammer should not be released.
• 10. Next, keeping your hand on the hammer, rotate the safety to fire. Now squeeze the trigger. The hammer should be released. Remember not to allow the hammer to fall under its own force. The hammer should only be

  

  released when the trigger is pulled.

• 11. With the hammer forward and the trigger pulled to the rear, push the hammer back down all the way until it engages the disconnector. Now release the trigger while holding the hammer lightly. The disconnector will release the hammer and the hammer should engage the trigger sear.

In the final segment of function testing we’ll go over a couple live fire tests that you’ll need to perform as well. If your fire control system has operated as described then you’re ready to move on to installing the buttstock. If you encounter any problems while performing the test make sure you have assembled the fire control system as we’ve shown you. If you still have issues consult the manufacturer, Tactical Shit, or take your lower receiver to a gunsmith familiar with the AR15.