It will be forced on the OEM ammunition and reloading components manufacturers. They will be be able to "stamp" each bullet and case with a unique ID at the time of production.
Sort of.
How the law is written, the firearm is meant to impinge, by a microstamp, a unique identifier on every round fired. These laws often do not specify whether it is the cartridge case, or the round, or both, that are meant to be stamped.
The unstated "theory" behind that, is that, if a fired bullet*and/or casing) is found where it ought not to be, the marking will identify the firearm that shot it.*
For that to work at all, there has to be a database of all the identifiers, which would then lead to a typical ATFE records search.The lawmakers carefully omitted any requirement for a registry of owners.**
Now, the above idea, to have bullets manufactured with identifying info or serial numbers, is very dangerous. It would be a way to "close" the handloading "loophole" that vexes every call for serialized ammo.*** Of course "we" have to resist, in every circumstance, all urges by government to meddle in ammunition sales (whole or in parts). That road leads to many, many bad things. The sericomic "You can have as many guns as you want, but only one bullet" being only one. Restricting ammo sales means less work for ammunition makers. Which, like any constrained industry will "bleed" talent to industries which are working.
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*Lawmakers have some knowledge on how to make laws, but not necessarily anything else. The fact that bullets tend to be malleable (and we often want them to be so) has escaped legislative attention. The distinct lack of ways to "stamp" a round that is fired (as opposed to merely chambered) is much ignored as well. This is only usefull if a company advanced itself and claims to be able to microstamp. "We" will then need to lean on them heavily to prove, conclusively, that the tech works. Otherwise it's vaporware, and the law can be stayed.
**There are a myriad of laws preventing centralized registration of gun owners. Which is a feat we owners and our lobbyists ought give frequent thanks for (even with their bruises and warts). So, most lawmakers make sure to not suggest that they want such registries. (They may hope for them, it is our job to thwart them at every turn.)
***"What do you mean 'What about cast bullets?' " The handloading community is resourceful and varied and quite skilled.
Our lawmakers do not understand (and I'm comfortable with not educating them) that the economies of scale in ammunition component manufacture tends to lots in the tens of thousands per each. Thus, any new marking scheme would take considerable time to see any results. Much like if there were an insistance to stamp a lollypop on every new-made AR, it would take many years before an appreciable fraction of ARs would all have lollypop stamps.
