Hey guys I recently ordered another lower from the Internet (spikes tactical) and it just so happened that the site had a gun shop I'd been to a few times already on file so my wife (christmas gift) didn't have to go thru all the faxing, calling, etc. now I've only been in this place a few times, so they don't know me, but I called them earlier to check and they said my lower was there, then the guy asks if this is for an SBR build... Now this is only the second lower I've had shipped to an ffl, but the other gun shop did not ask... Anyway I told the guy "No, it isn't, why do you ask?". He says the lower has SBR written on it?!?... I told him that it wasn't for an SBR, and that standard and short-barreled uppers use the same receivers anyway... What's up with this?