Ever had the bolt fall out of a disassembled AR 15 upper? I won’t forget the feeling; it’s sort of like a little version of when you almost fall backwards in a chair. With a centerfire AR upper it’s less likely to happen because the bolt should engage the locking lugs and provide a small level of retention. However, since .22 conversions are a blow-back action and therefore don’t use locking lugs, there is nothing to keep them from falling out when the upper is off the gun.
That’s how it happened to me. I most often use a discreet carry case to transport my rifle and frequently take along one lower and two uppers (a 5.56 and and a Tactical Solutions AR-22 LT). After all, there’s no sense in attraction unnecessary attention. In order to fit the rifle in the case, the AR halves are separated from the lower. Thankfully I was standing over my bed when the bolt fell out and it landed safely. I’m much more careful now but when I learned of the Black Dog Bolt Saver, I knew I was already a customer.
It’s a simple and effective solution for folks like me who don’t want to risk dropping their AR bolts (again). It consists of a L-shaped plastic bracket and two pins that cover the underside and rear of an AR upper in order to retain the bolt and as a side benefit it also somewhat prevents accumulation of dust, lint and such while the upper is off the lower. About the only change I’d suggest is a way to retain the pins when it is not being used. When not attached, the pins easily fall out of the bracket. Additional holes for pin storage or keeper lanyards would help. Just be sure you keep the ziplock bag it comes in for storage and you’ll be O.K.
Another feature I found is that because a .22 conversion doesn’t require a buffer, with the bolt saver in place it is possible to chamber-check the 22 upper. Best of all it’s downright cheap. Like chamber flags, it performs a needed service for just a few bucks so why wouldn’t you have a couple on hand?