ATF has a habit of ruling by letter, instead of the method Congress prescribes through the Administrative Procedures Act. Dave Hardy notes that in the case of 80% lowers, which are all over the gun news because of the raid on Ares Armor. It would be possible to do rule making on what a receiver is and is not, and have it be clear in the Code of Federal Regulations.
I don’t know how much you all know about these EP Armor polymer lowers, but it looks to me like they mill out the space for the trigger group, and then backfill it with a different color polymer so the customer knows exactly how much to machine. ATF argues that the milling process constitutes manufacturing a firearm, with all that it entails, regardless of whether you backfill it later. They have an argument to be made there.
But it’s quite disturbing that ATF was fishing for Ares customer list. What crime have the customers committed? Violating a determination letter? I know the courts have a habit of deferring to agency determinations, but how long is ATF going to be permitted to get away with ruling by letterhead instead of federal regulations like agencies are bound to?
I’d say good advice is, if you buy an 80% lower, cash and carry is the watch order of the day.