Just about every time I am assigned another G3 part to describe, it is like I am back in school all over again – ready to hit the books and learn something new. Sure there are those few times when I get a part like the G3 hammer or the G3 sear and I don’t have to stare at it for 20 minutes while scratching my head to figure out what it is and how it works. Then there are those other times; times like today, when I pick up the G3 bolt locking piece and scramble to discover its purpose along with all the intricacies that come with it.

After examining the part, doing some quick research and checking out a PTR91, I’ve come to the conclusion that the G3 bolt carrier group is a beautifully designed machine. The bolt head, locking rollers, bolt locking piece, firing pin and bolt carrier all fit together to form a metallic puzzle that works almost flawlessly. I could talk about it all day long, but today we’re here to focus on the G3 bolt locking piece.

The G3 bolt locking piece is located inside the bolt carrier. After cocking the G3 and readying it for fire, the bolt moves into battery. This is made possible by the bolt locking piece. As the bolt carrier group moves forward, stripping a cartridge from the magazine and pushing it into the chamber, the bolt locking piece is thrust forward into the bolt head and serves to force the locking rollers outward into small recesses. This ensures that the bolt remains locked into place during battery and until the firing sequence is initiated. Once a cartridge is fired, the bolt head is forced to the rear. This also forces the locking rollers inward and moves the bolt locking piece out of place until the cycle repeats. Additionally, the bolt locking piece serves as a guide for the firing pin. It is a lot to conceptualize, but in general, the G3 bolt locking piece manipulates the locking rollers and allows the bolt to move in and out of battery while serving as a guide for the firing pin.

Without a G3 bolt locking piece, your G3 won’t work as it utilizes a roller-delayed blowback system of operation. Keep an extra locking piece on hand to ensure your rifle remains in top-notch working condition for the low price of $7.95.