Why are most beam ballance scales 500 grain capacity?

[dickn52]

I'll take a WAG and say it's due to the length of the beam.

 

[1066]

For anyone interested in the finer points of beams scales, here's an interesting video showing the guts of the Prometheus powder dispenser.
At the heart is just a simple beam scale and interestingly the beam has a full scale of 0-110 grains.

 

[justinp61]

I don't think the beam length is it. I think a longer beam with a lower capacity scale could be made with different weight poises and pans/bracket. IMO it's more of a deal that this what they started with, it's well scienced out and it works. I also don't believe that any beam scale is more accurate in the middle of it's range. If it was on some kind of load cell or spring arrangement then yes there may be a sweet spot where accuracy is better.

 

[1066]

Quite right Justin. A longer beam with a lower range would be better. Manufacturers tend to supply the minimum they can get away with to maximise profits. A short beam with a smaller base means less material needed, cheaper handling and shipping costs etc.
If the available scales didn't work they wouldn't sell any, however, they do work just well enough.
What I'm saying is that I would like to see a better beam scale being offered. Reloading scale haven't really changed for fifty years but our accuracy expectations have.

Fifty years ago I think only a very small minority of reloaders concerned themselves with annealing, seating depth, neck tension etc. now we all use digital calipers and measure all aspects to two or three decimal places but the scales have stayed the same, in fact most of them are of poorer quality than we were using fifty years ago.

Here's a nice old Webster scale - 0-350 grains with adjustable sensitivity.

 

[JohnKielly]

most of them are of poorer quality than we were using fifty years ago.

I suspect that's because we don't want to pay any more for a product than daddy did 50 years ago.

There's a lot of quality product around - just not in gun shops. Something here should satisfy your needs: http://us.ohaus.com/en-us/products/balances-scales/mechanical-scales-balances

 

[dickn52]

Quite right Justin. A longer beam with a lower range would be better. Manufacturers tend to supply the minimum they can get away with to maximise profits. A short beam with a smaller base means less material needed, cheaper handling and shipping costs etc.
If the available scales didn't work they wouldn't sell any, however, they do work just well enough.
What I'm saying is that I would like to see a better beam scale being offered. Reloading scale haven't really changed for fifty years but our accuracy expectations have.

Fifty years ago I think only a very small minority of reloaders concerned themselves with annealing, seating depth, neck tension etc. now we all use digital calipers and measure all aspects to two or three decimal places but the scales have stayed the same, in fact most of them are of poorer quality than we were using fifty years ago.

Here's a nice old Webster scale - 0-350 grains with adjustable sensitivity.

Look at manufacturing costs, packaging, shipping and a happy medium was decided on. Then they looked at the loads being used and came up with the magic numbers.