I had a Rhino gas piston conversion 20 years ago. The replacement key had a pin portion that went in to the bolt carrier as using the bolts alone would result in sheared bolts. They would get knocked loose first too. The pin was a tight fit in a hole in the bolt carrier between the two bolts. The pin can be part of the key or maybe a separate pin but must fit both the key and the bolt carrier tightly. The gas key bolts aren't strong enough alone to hold up to a gas piston system.