M16/AR15 Ejector Modification
Have something better to do on Saturday than look for brass? Or maybe the guy to your right is giving you dirty looks as your brass go down his pant leg? Either way, a little shortening of the ejector spring will keep your brass close to home.
Remove the bolt from the carrier and, using a 1/16-inch pin punch, remove the roll pin that secures the ejector. The ejector SHOULD NOT fly across the room yet, but keep the palm of your hand in front just in case. The pin punch should replace the roll pin and keep everything together. When you withdraw the punch, the ejector should fly out - be ready for it.
This is what you should end up with. At the top is the spring, in the middle is the roll pin, and at the bottom is the ejector. The ejector is notched, and the roll pin rests in the notch. Most stock springs are 15/16-inch long. If the spring doesn't want to come out, bang the face of the bolt down on a block of wood, or use a sewing needle to work it out.
BUT, before you remove the spring, slide the ejector back in and see how far the uncompressed spring holds the ejector out. This is the amount to cut off. That is, shorten the spring until the loosely assembled ejector is flush with the locking lug faces.
Above is a spring (cut) & ejector slid into the bolt. See how far it now extends? The easiest way to cut the spring is with a Dremel or Fordam tool and a mini cut-off wheel.
Here is a cut spring and a stock spring.
Put it all back together and use a special roll pin installation tool (Channel Lock Pliers). Go VERY slow, it should not require much force. Make sure the notch is toward the pin and hold the ejector flush with the bolt face. Not as shown here, it's extending a little too far forward. After pressing the roll pin in, use your 1/16-inch punch to move the pin until it's ends are below the surface of the bolt.