In order to buy a firearm legally in California you must first successfully complete a firearms safety course, go through an extensive background check, find a licensed firearm dealer and wait out what I believe is a two week waiting period for handguns. But anybody over the age of 18 can walk into just about any major sporting goods chains store a purchase ammunition on the spot. It seems to me that if firearms have serial numbers, then bullets and casings should have some identifying markings as well. Imagine if bullets and shell casings had some some identifying serial numbers laser etched into them. To be able to tie a bullet, to at lot number, to a piont of sale, to a bar code, to a drive’s license and maybe to a murder. Something etched on the inside of thr casing and the "tail" end of the bullet itself. True crimminals obtain firearms illegally as a matter of course, but dare I say very few of them load their own amunition. Bullets that could be trace back to the purchaser.