Since the majority of 3 Gun rifles are AR-15 based, the number of rifle components is staggering. Every piece of the rifle can be modified or upgraded in some way. Triggers, compensators, hand-guards, and stocks are probably the most popular modifications. Magazine releases, bolt catches, charging handles, and QD sling mounts are inexpensive components that can greatly improve the ergonomics of the rifle. Even the upper, lower, and barrel can be swapped out to change weight or improve performance.