I am new at reloading and have a question about measuring powder. I have a RCBS 502 scale that measures from 0 to 500 grains. My Instrumentation pals tell me that when measuring for example 30 lbs pressure you do not use a 0 to 200 lb gauge, you choose a 0- 60 lb gauge so that you will be measuring mid scale. That will be more accurate. So as a comparison I am measuring 5 grains on a 0 - 500 grain scale. That's the first notch. Would it be more accurate to add a 200 grain weight to the scale and measure 205 grains to get the 5 grains?
Measuring Powder
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That's an interesting question, but I'm honestly not sure if it'd make a difference... I don't know enough about weights and measures to say if that's true or not.
I suspect that the scale is generally accurate enough without doing that, but if you want to experiment and report back, I'd be curious to know what you've found.
You may find the beam scale to be a big PITA... You may want to go digital. I shelled out extra for a digital scale, and I'm glad I did. If a beam scale is your thing, then...well, enjoy it
I suspect that the scale is generally accurate enough without doing that, but if you want to experiment and report back, I'd be curious to know what you've found.
You may find the beam scale to be a big PITA... You may want to go digital. I shelled out extra for a digital scale, and I'm glad I did. If a beam scale is your thing, then...well, enjoy it
The error in the tolerances of your balance will be well within reason, even for loading 5 grain loads. Your instrumentation buddies are correct that a balance with a narrower range would be more accurate & precise - but you're not splitting atoms, just throwing a few grains of powder. Same goes for digital scales.
Just use it.
Just use it.
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When I am using a balence beam scale, I use a check weight to calibrate the scale to the nearest half grain of my desired load. This simple proceedure gives me considerable piece of mind, particularly when two scales don't agree.
However in terms of replicating loads, it might be usefull to weigh 10 throw samples as a single weight. That should decrease the margin of error that comes from single throw weights. Given that most scales are only accurate to a 10th of a grain, a load weighing 5.1, 5.2 and 5.3 may all show the same to you on te scale.
The 5 grain measurement should be accurate if you properly zero it. These small balances are generally linear in their measurements. (A given movement of the counterweights equals a constant increase in measusement. )
Your instrumention buddies are correct that idealiy you should be at midrange of the device and that reasoning often applies to things like a pressure gauge (which is countered by a spring) or an electronic pressure sensor, which do not always have a linear output.
As A_O said, you are not splitting atoms.
Your instrumention buddies are correct that idealiy you should be at midrange of the device and that reasoning often applies to things like a pressure gauge (which is countered by a spring) or an electronic pressure sensor, which do not always have a linear output.
As A_O said, you are not splitting atoms.
