Frankly, I don't personally know whether this is true or not. But here's something I *do* know:I just can't believe you can look at a factory fired shell casing from a 1960 gun and then look at one from the same gun 30,000 rounds later and see anything that links the two casings....
Unless the gun is new when they compare to the shell database, i doubt that after some use, the case matches the gun anymore.
Im probably gonna get flammed for this, but I cant understand why some people have such a problem with this. Unless you plan on murdering someone with your gun, why does it really matter? I mean it probably has already, and will continue, to catch thousands of killers. Just my .02