Smyth Busters: Storing an AR With the Bolt Locked Open
12 days ago
Some members of the AR-15 community insist that storing an AR with the bolt locked open will damage the rifle's buffer spring. Leaving the spring under pressure, so the theory goes, weakens it over time, leading to unreliable cycling. Reality or myth? Don't worry, Brownells Gun Techs™ Steve and Caleb are here to settle the matter! It boils down to a similar situation to storing magazines loaded. Does leaving a spring compressed for a long time cause it to lose the oomph needed to do its job? Caleb points out that the AR-15 buffer spring is ALWAYS under tension. (Notice how you have to compress it in order to install it in the receiver extension, aka buffer tube?) It's just under more tension when the bolt is locked back.
Springs wear out through compression-and-release cycling, not through sitting compressed. If compression wore out springs, we'd have to put our cars on blocks when they're parked!
Storing the rifle with the bolt locked to the rear actually provides a big safety benefit: you can easily see the chamber is empty. When you step away from the line at a shooting range, an open bolt and magazine removed clearly show the rifle is unloaded and safe. If you do choose to store your AR-15 with the bolt-open, Caleb recommends doing so with the magazine out of the gun. A sharp rap to the buttstock CAN cause the bolt catch to release, letting the bolt fly home and chamber a round. Storing the gun with the bolt locked open ensures the rifle stays UNLOADED. If you need it quickly - for example, in a home defense emergency - you can easily insert the mag and hit the bolt release. If you want to store the gun loaded, do it with the bolt CLOSED and the safety on.
So today's myth is BUSTED. It's totally fine to store your AR-15 with the bolt locked back. It won't wear out the buffer spring, and you get practical "safety first" benefits.
For more discussion about spring longevity, check out our earlier Quick Tip episode, "Is It OK to Store Magazines Loaded?"