Calibration process for a Harrels powder measure

[halfmoanut]

Is there a procedure for calibrating a Harrels powder measure? I received no info with mine.

 

[TX65]

They are volume based dispensing devices. Consistency of powder drops is a result of technique. I was taught to lightly tap the handle 2 times before dispensing a charge (handle up) and 2 times after dispensing a charge (handle down). I only used the harrells for large kernel powders and found the tapping settled the charge and weights were more consistent.

Weight of charge depends on the density of the powder being used.

I always have a small electronic scale that I use to weigh a series of powder drops to determine the weight being thrown.

 

[LHSmith]

Advice on how to get best consistency with the Harrels is all over the map. I do believe my instruction sheet said specifically to NOT tap at either stroke.....and I don't see that method (tapping) used at matches. Best advice I have ever come across was to call Lynwood or Walter and ask them.

 

[MarkS]

halfmoanut,

No taping, Give Lynnwood a call. Did you get sheet on click values / per number mine was set on 6 per number. I get the start click vaule, say 30 + 2 clicks = 25 gr. of your powder. From there you just click up. This works great at the range. I find a load say 33 + 3 ckicks, that is all you need from now on. A lot of guy don't what there load weights, just the clicks.

Mark Schronce

 

[ReedG]

I'm not sure what you could calibrate on a Harrell's powder measure. You just need to find the number of clicks to give you the weight of powder you want. Your number of clicks may even be different than mine. I have a chart of what click number equals the charges I use of each powder and they are absolutely repeatable.

I've loaded thousands of rounds with my Harrell's and under no circumstances would I tap on the up or down stroke. I set the measure up on a TV tray when I first got it and threw hundreds of charges with an electronic scale to get good consistency. With Varget, Benchmark, H4198, H322 powders this thing is a marvelous piece of equipment. I've never used other powders and cannot speak to using one with them.

 

[tiny68]

I build calibration plots by running my 4 most commons powders all the way though the range a BR case would use. I did them at every 0.25 clicks to start, then 0.5 clicks, only each full click on the remaining powders for the whole range. Very linear. I usually do load development at home with a my Chargemaster, but found it difficult to use in windy environments (every BR match I have been to). Here is what my plots look like. I have them taped into each log book and the lid of my range box. I find they value to get close with having to mess with a balance at the range. All weights were measured with my Ohaus (0.001 gram readability).

In terms of use, Linwood told me no bumps, go very slow and consist on both the strokes. Has worked excellent for me.

Luck, Tim