right, whats your defence (lol) budget this year?Literally every single gun already sold would be grandfathered in and exempt from that law.
Let's assume it costs $2 to build, ship, and install a chip in a gun.
There are > 350 million guns in the US.
That'd be more than 700 million dollars. It'd be cheaper to hire guards and buy metal detectors for all the public schools in the US.