I have multiple rifles chambered for a single cartridge and have 100 dedicated cases for each hunting rifle and either 200 or 300 case for each varmint rifle. The cases are dedicated to each individual rifle and never fired in a different rifle. I'm not saying that this is the best way to manage your brass, just that it is the way that I do it.
Three chambers cut with three different reamers are more likely to be slightly different than they are to be exactly the same. When you're working in 1/1,000" tolerances the differences may be small, but even a very small different may keep a cartridge from chambering.
