MGI D-Fender Extractor Enhancer AR15 O Ring AR-15 Defender
The D-Fender "D-Ring" can assist in eliminating extraction problems in the M16, M4, and AR15. This High-Tech, composite "D-Ring" increases extractor spring force by 4x!
Insufficient extractor tension can cause cases to be left in the chamber or dropped loose into the feedway where they get in the way of the next round. Your extractor should have a little rubber bumper inside the spring. That bumper should be blue or black in color. If it is missing or is some other color, replace the spring with a new one. I also highly recommend a small D-shaped polymer donut, the MGI D-Fender, which rests around the extractor spring and greatly increases extractor tension.
Years of testing and evaluation have gone into the D-Fender project. The material that the D-Fender is constructed of will not break down under normal weapon operating temperatures, nor will it melt from cleaning solvents and lubricants. It will not become "squashed" from the pressure of the extractor, or become dislodged causing the weapon to malfunction. Built with the Professional in mind, and the understanding that any failure in your weapons system can mean the loss of your life. This is another simple inexpensive fix that is a MUST HAVE for your AR-15.