Here's what it's all about (once more):

Three guys in Seattle (or thereabouts) hatch up the idea, "what if the same technology the post office uses to identify mail were applied to bullets and cartridge cases?" (Line of thought being it'd be easier to tell which policeman fired the fatal shot, or which Soldier, or which criminal, ...). So, they PATENT the idea (not the actual equipment or process) and hire themselves a law/lobbying firm to "champion" their case to state legislatures. Oh, did I mention the part about a "modest" $0.005 tax per round of ammunition that would "probably" be passed along to the consumer. Oh, and there's the part that this technology, while having been applied in small scale, hasn't been applied in a production/manufacturing environment where most reasonable people with any knowledge of manufacturing processes tend to think it'd be impossible to achieve total quality control or accuracy. 8B rounds per year at that rate puts about $8,000,000 in the three guys' pockets annually - for doing nothing but hatching a hair-brained idea and then "patenting" it.

Fortunately, it appears that most states where this "legislation" has been introduced have shot it down, let it die in committee, etc. Nonetheless, be on the lookout for it.