RE: Zeroing Scales
Yes, use SMKs, they are very consistant weight-wise. For the price of a set of check weights you can buy a whole box of them, purpose made check weights are really a gimmick you can live without.
BTW, as with anything else, scales have tolerances. Most of them are rated for 1/10th of a grain of error. Its very well possible that you could take two identical scales and have one read 1/10th of a grain low and the other 1/10th high giving a 2/10ths difference in weighing the same object. The best you can hope for is to zero the scale against something of a known weight (like a SMK- I keep a single one in a box just for zeroing my scale) to keep your reloading data consistant.