Powder measure and scale not jiving.

[LynnMassGuy]

The powder ammounts that I dispense with my Lee powder measure always seem to weigh about a grain short of what they should. Would I be better by calibrating my powder by dispensing a measure and then weigh it on a scale to calculate the VMD as opposed to relying on the VMD's supplied by Lee.

 

[mtnbkr]

Yes. I've never seen the chart supplied by Lee match what my scale says. I've never been a full grain off (make sure your scale is calibrated properly as well), but a few tenths is common. Fine grained ball powders come closer than large grained stick or flake powders.

Chris

 

[LynnMassGuy]

Thanks.

 

[NavajoNPaleFace]

There are some calibration weights sold out there.

I believe the set I bought were RCBS...but I'm not 100 percent positive.

I like the idea of knowing my scales are 'right on'.

I have never gotten to the point where I could trust dippers and even my RCBS powder dispenser is often off but seldom over .1-.3 of a grain. That's close enough for plinkers.

For precision loads I will hand measure each load to 'right on'.

 

[lee n. field]

Is that the set of Lee dippers? My experience with them is that they weigh lighter than Lee's docs say.

I agree, get a set of check weights, and make sure your scale is accurate.

 

[stans]

RCBS makes a nice set of check weights and they are a wise investment in your continued enjoyment of reloading and shooting safely.

 

[LynnMassGuy]

Check weights sound like a good idea.

 

[birddog]

My Lee Auto Disk Powder Measure is highly repeatable and never varies noticeably at all, HOWEVER, with Red Dot, Unique and Clays, it does NOT match what the Lee chart says it should be putting out (I verified this on 2 separate scales).

With Unique in particular, for the most part I get a whole grain less than what the chart says it should be dispensing.

I'm sticking with the Lee, however. As long as I know via weighing what each disk setting is throwing, it's is extremely consistent charge to charge.

 

[LynnMassGuy]

The powders I am having the problem with are Green Dot and Herco.

 

[Poodleshooter]

Does everyone else actually pay attention to the charts? The weight will vary vs. volume due to all kinds of factors that the powder measure's manufacturer can't control. I make one calculation to get an estimated volume for the charge weight I want. I then simply weigh thrown charges and adjust up and down by feel until I can reliably throw the charge weight I want. It usually only takes about 4 throws and adjustments, and seldom has anything at all to do with what the charts say.

 

[1911Tuner]

When in Doubt

Trust the scales...and check them with the standards on every set-up or change of charge weight if you're putting together top-end loads for a
rifle or magnum revolver. Even atmospheric pressure, temperature and humidity has an effect on the scale, and what a given charge weighs from day to day.

The powder measures' published charge weights are nominal. You can't count on them to be dead on with a given lot of powder because canister
powders vary in density and moisture content from lot to lot. A fixed
rotor setting will throw 15 grains of one lot of 2400...and 15.2 or 14.8
with another lot.

Be CARE-ful. Your eyes and fingers can't be replaced. Ain't preachin'...just don't want anybody gettin' hurt. I consider all shooters and RKBA advocates as my brethren, and I worries about ya'll...