I’ve personally experienced “hammer-follow” while shooting a 100% original, absolutely no modifications or after-market parts Colt AR-15 (not mine, by the way, so please, Mr. ATF agent, don’t go knocking down my door tomorrow night). It was sorta funny at first, having the rifle blip off two rounds at random, but it’s also a little nerve-racking to think that some busybody might squeal because you have a “machine gun” at the range. If you have a similar problem, it’s best to get it fixed asap.
And of course, the very same judicial system, and the very same judges, who decide that any tiniest flaw in your weapon is a felony.... is also the same system, often the same *individuals*, who hold that the police can’t be held accountable for protecting you.