Newbie needs help with beam scale accuracy/calibration

[johnsopa]

I have a Hornady Magnetic Scale that has been serving me well. It reads the same powder load consistently.

When building my first 0.1 grain increment ladder today for my 223 loads, I noticed that 24.8 grains is measure the same as 25.0 grains and 24.9 grains is measure the same as 25.1 grains.

What I mean is that when I have the scale set to 20 grains plus 4 grains plus 0.8 grains,24.8), then set the scale to 20 grains plus 5 grains plus 0.0 grains,25.0) -- essentially, I reset the tenth of a grain weight to zero and then moved the 1 grain weight from 4 to 5 -- the same powder load is shown at zero, instead of showing up as 0.2 grains lower.

Hopefully, I am explaining this correctly.

Is there a way to fix this?

I was trying to build a 0.1 grain increment ladder from 24.5 to 25.4 grains, so I set the scale at 25.0 and just used the over/under readout where the beam pointer is to build my ladder. I didn't move the weights at all.

Thanks,

John

 

[Lane]

I have a Hornady Magnetic Scale that has been serving me well. It reads the same powder load consistently.

When building my first 0.1 grain increment ladder today for my 223 loads, I noticed that 24.8 grains is measure the same as 25.0 grains and 24.9 grains is measure the same as 25.1 grains.

What I mean is that when I have the scale set to 20 grains plus 4 grains plus 0.8 grains,24.8), then set the scale to 20 grains plus 5 grains plus 0.0 grains,25.0) -- essentially, I reset the tenth of a grain weight to zero and then moved the 1 grain weight from 4 to 5 -- the same powder load is shown at zero, instead of showing up as 0.2 grains lower.

Hopefully, I am explaining this correctly.

Is there a way to fix this?

I was trying to build a 0.1 grain increment ladder from 24.5 to 25.4 grains, so I set the scale at 25.0 and just used the over/under readout where the beam pointer is to build my ladder. I didn't move the weights at all.

Thanks,

John

John: Personal point of view, your working to hard!For small cases like the .223 Remington work in 0.2 grain increments. Your start load should be based on your maximum charge weight, minus a decrement that is correctly 20 times the increment. Your increment is 0.2 grains. 0.2 x 20 = 4.0 grains. The point of the ladder test is to prove out a load that is accurate with minor powder charge weight variations. As long as the minor powder charge weight variations keep a specific bullet weight with in a velocity range. Your powder measure technique can be + or - 0.2 grains over under your target powder charge weight and will still keep a specific weight bullet with in a velocity range that will cluster all it's bullets. You can fine tune the load,barrel time) later by other means in your loading technique, sizing technique, bullet seating depth etc) 0.1 grain increments defeats the advantages the ladder test proves out. Your problem makes the very point the ladder test accounts for. You have made the choice of bullet type/weight,powder,primer and case. All you are after now is to identify a powder charge weight,velocity) the assembled components like in your particular rifle. Wish you all the best Lane