While it is denied, many are of the opinion that an unofficial record of gun owners and their weapons serial numbers is being created/maintained. I have heard it called "officer journal notes" ect. An officer "taking" your firearm will normally go to his car and "run" the serial number to "check" if the item has been reported stolen. Again, the court cases you have been given show he must have RAS to do this UNLESS you willing hand over the item.
Reasons for asking, more times than not "officer safety" - they are uncomfortable with you having a firearm so they would like you to surrender it to their safe keeping for the remainder of the encounter. The LAW doesn't require you to do so but what the heck, they can ask, and if you say yes, well, might as well run the number through the criminal data base.....
Answer to the "I would like to go ahead and hold the weapon during the remainder of this encounter, it is really for both of our safety....." is "Officer ________ (hopefully you can get him to provide his name), I understand your concern, but I believe the item will be much safer for all parties the less it is handled. I believe the safest place is for it to remain in it's holster." As others have stated, if the officer insists, refuse to touch the firearm but inform them they can physically remove it from you. Also a good time to ask if you are free to go. Make sure you get the officer to state his name for your recording device. It is a judgment call, with every situation being different, as to whether you "choose" to let the office know you are recording the conversation. Some that are bullying and pushing the legal limits will back off once they know a record is being kept of the conversation, others may respond by acting worse. As another response indicated, the side of the road is not where disagreements on the law is to be won, get through the encounter without "surrendering" any of your rights and follow up afterwards in the courts if you believe your rights were infringed.
