Find one who is an aeronautical engineer and not some yahoo and we can listen to their opinions.
You rang? A properly done rivet is almost always more sound than a bolt. The simplest explanation I can come up with is that bolts leave wiggle room, while rivets mold themselves to the hole, thus properly transferring forces. I'm not going to pretend I know anything about AK builds, but if it were my build I would play it safe and rivet.