I have an old RCBS 10-10 scale which started sticking on me, so I honed the pivot edges, which fixed that issue. It still has a problem in that trickling powder into it to come up to charge doesn't work well. I have to bring the pointer almost up to zero and then bump the pointer to get an accurate reading, and I keep on doing that until I get a perfect zero. Slow, but it works.
Because of these problems I bought a Lee Safety Scale, which I've heard is very accurate, and some check weights.
I zeroed both scales, set check weights that were as close as possible to the load I want in the pan, and both scales were off maybe .15 grain, so they agreed with each other, but not with the check weights.
I could, at this point, leave well enough alone, and just use the 10-10 scale and not worry about it being a little off. (I set aside the Lee scale because it is fiddly, hard to set, and even though it responds well, it takes so long to settle that it isn't really any faster than the RCBS).
What I did was place the check weights in the pan and set their weight on the poise, and then used the leveling screw to get the pointer in the right place. I think that's correct but it got me thinking. If I were to take the weights out of the pan and set the poise to zero, the pointer would be off. So I'm wondering if leveling the scale and zeroing is even important when you use check weights, for that one weight.
Also, you can also adjust the pointer by changing the poise setting, although it could be confusing to have a different poise setting than the actual charge weight. But it seems to me you could actually do any combination of using the leveling screw and changing the poise position to set the pointer -- it doesn't matter --whatever you do, your charge will be accurate. But since it wouldn't be accurate with an empty pan, it obviously wouldn't be accurate at any other weight than the check weights. Is all of that correct?
Or, I could do what I've read described as a calibration where I would add or subtract weights from the pan support. But I have no idea whether that is actually making other weight points accurate, or if it is just used to allow you to establish the initial zero but doesn't change any other weight readings.
Any thoughts or suggestions?
Last edited by postoak; 06/10/23.
