I don't make many post here, but I ran into this problem. I built an AR upper last summer in .458SOCOM, and was sharing it with my DPMS oracle lower for the time to save some cash. I decided to finish it up and buy an AR lower from a fairly high end custom gun shop that now offers their own AR-15 brand. The shop is Modern Outfitters located in Meridian Mississippi, and they're opening another location in Dallas, great shop and great people, I would suggest stopping in if you are ever nearby, reasonably priced lowers also. While I was in town I swung by to pick up a stripped lower, and they realized part way through that I couldn't buy it because I'm 20, not 21. They said their understanding with their ATF agent is that a person must be 21 to buy a stripped lower, because you can build it as a pistol. Is this correct, and has anyone else had this problem? I'm fairly educated on the gun laws but never even considered this. However with the amount of redundant and ignorant gun laws it doesn't surprise me. This just seems as dumb as requiring a person to be 21 to buy .223/5.56 because you could possibly put it in an AR-15 pistol. Oh yea even if I was 21, if I'm correct this would also mean I still couldn't buy it, because the shop is in Mississippi, and I live in Alabama. I would then have to have it shipped to an FFL in Alabama and then could pick it up. It sure is easy to accidentally commit a felony these days.