RE: Zeroing Scales
If you are working up your loads like you are supposed to be doing, you don't need the scale to be dead precise to the 1/10th gr (as I mentioned before, the balances aren't that precise to begin with)- you need it to read the same every time which is more important. And yes, Sierra Match Kings are very consistant- I've weighed samples of 30 or more bullets from each box of 4 different calibers/weights and if I find 1 out of every 30 that doesn't weigh the same as the others, its a suprise.Spend the money on another relading manual, or a box of SMKs and test this for yourself. Don't waste your money on check weights.
BTW, I work in a place that uses a lot of analytical balances, some read to 0.000001 gram, I've made up my own set of check weights from coins, paper clips, and other objects and havebeen careful enough to clean them before assigning them a weight value and handled them with only goves. I've tested them against SMKs enough that I eventually got to the point that I no longer use them and only use bullets to check my balance.