Originally Posted by hometheaterman

The bolts on them were made of harder metal than the receiver rails it rides on. This overtime chewed up the rails, and caused them to become jam o matics and essentially worn out. They also have a reputation for getting chewed up where the locking lugs on the bolt hit the receiver. If you have one that works, I'd keep it. However, if buying one I'd be very hesitant, and I'd be very careful when inspecting the gun, and I'd prefer to shoot it before buying it.