I read an article on this several years ago, I think it was Popular Mechanics or Science or whatever.
The one way that this MIGHT be successful is if the OEM just did it and told no one but the ATF.
It would take awhile before the cat got out the bag, but in the meantime they could pile ups some convictions.
The technology is there and it does work. The article pointed out though, like most here, that it really is impractical.
Well, they’ve had the predecessor to this, the ballistic fingerprint system, for about a decade now, and it still hasn’t resulted in even ONE conviction of a citizen who was using his own gun in a crime.
It has, however, proved embarrassing for a number of police officers, though.