Scenario:
I have a registered lower with a 11.5" upper in caliber “X”. I built a pistol with a 8.5" upper in caliber “XX”. Can I take the 8.5" upper and install it on the registered lower without any repercussions?
Reason:
I would like to use caliber “XX” to hunt with until the stamp (SBR) comes back for the pistol lower.
Does the caliber and overall length mean anything on the paperwork? Or is swapping uppers and not worrying about the caliber/length legal?
I apologize in advance if this has already been asked. If so, please direct me to where ever I may find my answer. Thanks