Senate Bill S2742 includes "The Usual Suspects" of impositions upon the Second Amendment: however, this bill is (so far) unique in that it specifies the affected calibers:
The calibers covered by the coding requirement shall include: .22, .25, .357, .380, .40, .45, 9 mm and 10 mm.
Going out on a limb here, I'll assume that this clause is high-level specific. That is, when it includes ".22", it does not include (for example) .223, .222, .22-250 etc. calibers. However, nothing in the text of the bill specifically excludes these notionally rifle calibers. I also note in passing that the 50 million+ rounds of .22 rimfire ammunition manufactured annually is not generally considered a threat to public safety, suggesting that the bill is intended only as an imposition of unrealistic and unjustified regulation on the ability of firearms owners to purchase ammunition for their legal firearms at an economical price range. Well, that goes without saying.
The activation date of this bill is January 1, 2009; by January 1, 2011, all 'non-encoded' ammunition must be 'disposed of'.
The only other significant characteristic worthy of note is that the bill does not also require that the cartridge case be 'engraved' with the same unique serial number as the bullet.
This bill was introduced on February 26, 2008, by Senator William A. Walaska.
If you live in Rhode Island, write your state legislators.
Come to think of it, write to Bill Walaska and suggest he immigrate to Alaska.
Sorry ... that last was a disservice to the law-abiding residents of Alaska.
Oh, by the way, Rhode Island isn't content with introducing Encoded Ammunition legislation.
S2720 and H7834 are companion bills which require Microstamping of ammunition, based on engraving of the firing pin AND breach face of semi-automatic weapons. This is a copy of the law recently enacted in California, similarly ineffective, and as you have probably already decided is both overkill and 'under-possible'.
Rhode Island residents are hereby given permission for being embarrassed by the perfidy of their state legislators. Well, they are politicians, they have been bought and they will do anything ... anything at all ... to get their names in the newspapers.
The legislators in my state are generally no more endowed with ethical constraints than those in your state. If this goes on (as Robert Heinlein was fond of saying) there is no reason to expect that similar egregious and tyrannical bills will not be introduced 'here'.
Sorry. "The Tree of Liberty", and all tha.