Here’s a possible twist for ya
@Alex that might have messed up the pawn shop employee … legally you can’t buy a striped AR receiver if you are under 21 ... but you are correct in that you should be able to buy a complete AR. Also nobody can buy a receiver outside of their home state from an FFL without it going thru an FFL back in the buyer’s home state but you can buy a complete AR (per state laws). It all has to to with the little box the FFL checks on “type of firearm” … “handgun (receive, frame, etc)” , “long gun (rifle or shotgun)” or “other firearm” … and how “receivers” are handled under the “other firearm” and limited age and resident restriction.
I could not buy just a stripped AR receiver from PSA for a build when driving thru SC but I could buy a complete AR, mag and ammo and walk out of the store ready to rock … make perfect Democratic sense