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Author Topic: Powder Weight Question (Universal Clays)  (Read 1694 times)

Offline Eagle1

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Powder Weight Question (Universal Clays)
« on: August 28, 2010, 11:24:23 PM »
I am tinkering around getting ready to start reloading 9mm. I have some Universal powder and thought about starting with it. Now I have purchased more equipment in the past year than I have used yet. That said, here is what I ran into tonight.
The load data stated I needed 3gr of universal. I used both a Lee Perfect powder measure and a Hornady powder measure. Then weighed each on my Franklin electric scale which read 4gr+. Not believing the scale after calibrating it numerous times I grabbed my antique Redding/Hunter beam scale. Zeroed it and found it to read the same as the electric scale. Still not sure of this I broke out the Lee Safety Scale (see I told you I have bought more stuff than I have used) and it read the same as the other two scales. This can not be common to be off by 33%. That would put me way over the save limit with this powder. Has anyone else been this far off with Universal or any  other powder. Just goes to prove you should always weigh your powder.   
Thanks for any help you may share.
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Offline Dan W

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Re: Powder Weight Question (Universal Clays)
« Reply #1 on: August 29, 2010, 10:58:27 AM »
Typically, I would throw 3-4 to stabilize the measure, then weigh the next 3-4. I pay no attention to the scale on the measure except as a reference point. I only go by the actual weight thrown. I then adjust the measure to throw the weight desired. rechecking several times until I am satisfied the charge is correct.

If the scale says the charge is too heavy, why don't you simply adjust the measure to throw less, until you get down to 3gr.

BTW, I would trust a beam scale over a digital if there is any question
« Last Edit: August 29, 2010, 10:59:25 AM by Dan W »
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Offline SemperFiGuy

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Re: Powder Weight Question (Universal Clays)
« Reply #2 on: August 29, 2010, 11:28:27 AM »
Eagle1.......

It appears that you do indeed have a pretty consistent charge drop of 4+gr, judging by the agreement between your three scales:  electric and the two beam scales.

From the Hodgdon loading tables, it appears that you want to load 147gr Hornady XTPs @ 800fps, which is a 3.0gr powder charge.   Nice, conservative, low velocity target load.   Here's hoping that you don't have any 4+gr charges loaded, because that load is off the chart for those heavy bullets.   Might have to use your bullet puller, if so.   Or dump whatever is already loaded.     

You probably know all this already:   If you're using the micrometer on the Lee Perfect Powder measure as the primary indicator of the charge weight, it just doesn't work that way.   The LPP measure drops the powder charge by volume, not weight.   No matter what the charge micrometer gauge on the charging handle reads.   When setting up, you gotta drop a test charge first, then weigh and adjust the micrometer until the charge weight drops just right.   Basic reloading procedure.   Which you most likely know.

If you drop a long string of charges before rechecking the charge weight, some powders actually "pack" in the powder charge chamber and become more dense.   It's the pepper shaker effect.   If you fill a pepper shaker full to the top, put the lid on, and tap it on the table top, shortly the pepper will pack down and a space appears at the top of the shaker.   The pepper is now denser and a given volume weighs more than previously.   Same w/some powders.  Happens because of the tapping effect from the charge handle.

So--you might be experiencing that kind of phenomenon.   Or, if the micrometer isn't locked, constant tapping may open the charge chamber to larger volume.

You said it best:  Weigh the powder charge.   Every few charges, at minimum.  [Beam scales properly zeroed out seem to be the most honest.]

And---doesn't sound to me like you have too much reloading stuff.   Not yet.


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Offline unfy

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Re: Powder Weight Question (Universal Clays)
« Reply #3 on: August 30, 2010, 10:51:56 PM »
I'll echo not trusting a volumetric charge weight guess knob.

An electric scale with tear feature is great. Size and prime the brass. Throw your charge, adjust, throw etc until the scale says what you want. Then throw another 5-10 charges and make sure you're still at desired weight.

If a volumetric thing shows weight increments - each powder has a different density.

Inconsistent charge throws can be human error (not cycling the same way each time), humidity (powder sticks to tube or cavity in thrower, or itself), or static (dryer sheet can help).
hoppe's #9 is not the end all be all woman catching pheramone people make it out to be ... cause i smell of it 2 or 3 times a week but remain single  >:D