for grins, with my cabelas points I got a RCBS wieght scale check set. Came with variety of calibrated wieght from .5gr to 200gr. And you can put them all on there for 498.5gr. Using the larger counterwieght I was dead on with my 505. In other words, measureing out things in increments of 10gr. But using my middle counter wieght (i.e. 1g increments), it was off by .05gr. Reason I know its .05gr is I would move the smallest counter and it would be overwieght or underwieght when I moved smallest counterwieght.

Thats pretty good for a 45 dollar scale. But now started thinking, its a waste of money for this scale check kit. After I verified my scales, won't use it again.