Re: Digital scale information?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ChadTRG42</div><div class="ubbcode-body">Look into an AccuLab 123 type scale. It's accurate to .02 grains. You can have the RCBS CM throw the initial charge .1 to .2 grains low, and trickle up on the AccuLab. It works for me.
I would find it very impressive is a $20 scale was truely accurate to .02 grains. </div></div>
For me (and most of us), it honestly doesn't matter one hoot if it's accurate to .02gr. What matters is the precision. If the scale will read a given test weight the SAME every time, 99% of the battle is won.
I have had this scale a while. At first, I tested it against my RCBS 10-10. Once satisfied it was close (real close), I worked up loads using it. When I found 45.5gr Varget (according to the scale) worked great consistently, I filed a penny down so that my scale registered 45.50gr. Before a reloading session, I ensure that penny reads 45.50. It always does. I mean ALWAYS. Thus, it is highly repeatable AT my intended weight.
Maybe that penny ACTUALLY weighs 46gr. Maybe it weighs 100. I don't care! As long as my charge reads 45.50gr on the scale, I've got a safe charge that will be highly accurate.
By the way, my family business is the force transducer industry. I know something about them. There is no extra magic or voodoo in a $500 or $1000 electronic scale (with capacity higher than a gram or two - the scales that masure really really light stuff is a different story) than a $20 one, and price has *very* little to do with accuracy or precision - particularly precision.
For a load cell to work, the resistance across the strain gages must vary LINEARLY with force. The more linear, the more accurate (not precise) it is. It is a cake walk achieving .1% The best is .02%, and you can try all you want, but you'll only get one that good on rare occasion. When you do, you set it asise, and sell it as a super premium transducer to a customer that *thinks* they need one that good.
.1% of 50gr is .05gr, which is ENTIRELY sufficient for what we do.