Bolt Catch Plunger Spring

The Bolt Catch Plunger Spring goes with the bolt catch plunger to put pressure on the bolt catch.  This is one of the springs that usually comes in a lower parts kit.  Here is a picture of the spring:

Bolt_Catch_Plunger_SpringYou can purchase a Bolt Catch Plunger Spring (click here for Colt version), or click here for DPMS version, or click here for a spring kit option from Amazon or you can get a Lower Parts Kit.

Here is an image showing the installation of a Bolt Catch Plunger Spring with the Plunger and Bolt Catch.

Installation of AR15 bolt catch detent and spring