We asked Brownells Gun Techs Steve and Caleb bring their unbeatable combination of wisdom and good looks to answer an important question: What spare parts should I keep on hand for my AR-15? Gas rings and buffer spring wear out through normal use, says Caleb. And he has a handy rule of thumb for telling when that buffer spring needs to be replaced. Most likely to fail on the bolt / carrier group are the extractor spring and pin. The cotter pin and cam pin can break, but more often they get lost when the BCG is disassembled for cleaning. Steve says he's tried but has never succeeded in getting an AR-15 firing pin to break.
Downstairs on the lower receiver, have spare springs and detents for the pivot / takedown pins. AR-15 hammer and trigger springs rarely break, but if you're using lighter-power springs, keep standard-power spares on hand. If your rifle stops working, swap in the factory-spec springs to find out if the problem is the gun or your ammo. The buffer bumper pad (say that three times fast!) can wear out in certain circumstances; Caleb explains. Steve's Wisdom: If you've upgraded your trigger, keep the original one as a backup spare. For the other small parts, pins, and springs, keep spares on hand mainly because they can get lost when you've got the gun disassembled for cleaning. Why lose a day at the range when you can reach into your ditty bag and swap in a spare in a few seconds?
Are there any parts the guys haven't mentioned? If so, tell us in the comments below.
