Measuring Powder

[asimpleman]

I was setting myself up to load some ammo for the first time and after tumbling/cleaning, sizing/depriming, and cleaning the primer pockets I came to measuring the powder. I have the Lee perfect powder measure and the Lee safety scale. I read the instructions for both the powder measure and scale, set them up, and zeroed the scale (with the measuring pan on it). (This is neither here nor there but I was using IMR 4350 for my 30-06 with a 150 grain jacketed bullet) I looked at the powder conversion charts that came with both my Lee dies, Lee reloading manual, and Lee powder measure. The starting load for this powder and bullet weight stated that I would needed 54 grains of powder/ 3.97 cc. On my scale (since it is a measure of grains) I set it to 54 (with the measuring pan on it). For my powder measure (since it is in cc) I set it to 3.97 as stated by the instructions. I poured my powder in the powder measure hopper and ran a few cycles through it just to coat and break it in. I then threw one charge into my measuring pan and weighed it. The charge was way to light. I threw another charge just to make sure it was consistent and it was also to light. So, since it was to light, I put the powder measure on 3.98( to light), 3.99 (to light), 4.00 (too light), then 4.40 ( almost there), 4.43 and then I got it right on 54 grains. For consistency I did this another time, and it was way too heavy!?:banghead::banghead:
So, in general, does anyone know what I am doing wrong or trick/techniques that they use for their Lee powder measure products. I want to be accurate on the powder for safety and for accuracy but all my attempts to measure a decent charge were off. Thanks for your input.

asimpleman

 

[USSR]

There is zero relationship to any numerical markings on powder measures and the charge weight they will throw. So, first confirm that your scale is correct (weigh some bullets of a known weight), then trust your scale and set your powder measure to whatever numerical setting produces the charge weight you desire.

Don

 

[rcmodel]

You simply cannot rely on volume measure weighing what it is supposed to weigh.

Every lot of powder may have slightly different density due to moisture content or solvent content left in the powder.

Then after you open the can, it can evaporate out and get less dense, or absorb humidity and get more dense.

Then, you go buy another can of the same powder and it has a different Lot# on the can?
Guess what?
Right, it probably won't "dip" the same weight as the old Lot# can.

They make & blend each powder lot to produce the same energy & burn rate as previous ones.
Not to always weight or dip the same.

That is why we have to trust the scales to be right.
Not the CC markings or dippers Lee uses.

Lee's load data is purposely made light, to make up for over-charge "dips" of more dense powder lots.

rc

 

[Harley Quinn]

Pick one, fill up with powder, then pour out and weigh, do several and see how close it is for your wanted loads... If middle of road power, will be fine...

I always went light and trickled to desired charge...Most of what I loaded was pretty hot

Agree with below mention...

***Lee's load data is purposely made light, to make up for over-charge "dips" of more dense powder lots.***

Regards

 

[RandyP]

When I am setting my powder dispenser I throw three charges at a setting and dump the powder back into the dispenser and then weigh the 4th & 5th. If it needs adjusting I adjust and then throw at least three and weigh the next two.

I use an inexpensive digital scale - my old eyeballs don't like the Lee beam device - lol - which is a $30 MTM DS-1250 model. Works great for my needs.

I should add that I have NO interest in max loading any caliber. All my reloads are low-mid range plinking loads and any slight variances in accuracy are unimportant to me.

 

[rcmodel]

On that note.
I always throw 10-15 charges after filling the powder measure to get the powder settled in the reservoir like it will be when I start using it for real.

Then I will throw 5 in the scale pan, then divide by 5 to get the average weight of a single charge.

Then adjust and do another 5, average, and fine tune again.

Much more accurate then just weighing one charge each time and adjusting.

rc

 

[RidgwayCO]

When I was using a conventional powder measure, I used the method rcmodel described above. Averaging five or ten throws keeps you from chasing individual powder throws all over the lot. Try to ensure the powder is settled before starting your averaging routine. And remember, plus or minus .2 grains per throw is pretty good with a powder measure (and I know, some will do better). For your .30-06 load, I doubt you'll see a difference on the target, and I'm sure your quarry won't feel the difference...

 

[GLOOB]

Then I will throw 5 in the scale pan, then divide by 5 to get the average weight of a single charge.

Then adjust and do another 5, average, and fine tune again.

Much more accurate then just weighing one charge each time and adjusting.

Bing, bing, bing!

I do the same, but I do ten throws (pistol; I guess 10 rifle loads probably wouldn't even fit in the pan!). When you can get ten throws to agree within a few tenths a couple times in a row, then you know you're in the ball park. After that, you can weigh out some individual charges to see how large your variation is.

Unless you are intent on weighing out each individual charge, then the best you will get is a bell curve. You just want to make sure you 1) set your bell in the middle, and 2) that the extreme highs and lows are going to be acceptable.

Also:
- Shake the powder dispenser after you fill it. Large flake powders take some time to settle, unless you shake them very well.
- When adjusting the screw out, you're uncovering "virgin" measure area that has not yet been coated with powder. So the first several throws might be off.

 

[medalguy]

If you have a new powder measure, run at least one hopper full of powder through the measure to coat the whole thing with graphite before you start serious loading. This may take you a lilttle while but it sure will make things even out.

It's an excellent idea to fill up the powder measure and then throw at least 10-15 charges to allow the powder to settle into the measure before you start loading. Put the trial charges into a paper cup and just pour it back into the hopper. Also if you don't have one, be sure you put a powder baffle into the hopper to help even out the downward pressure on the powder to even out the charges.

Finally, however you use your powder measure, BE CONSISTENT! If you tap it twice between every load, do that the same way every load you throw. If you stand on one foot and bang the hopper with a ball peen hammer four times between every load, just do it that way each and every time. It's not nearly as important what you do but be consistent in how you do it.

 

[Lost Sheep]

I am sorry to say that USSR (post #2) is wrong when posting that there is zero relationship. There is a relationship. Unfortunately the relationship is not as tight as Richard Lee would have us believe.

USSR is also correct that the relationship should be verified with a scale every time you start a loading session, and periodically during the session. As you approach any extreme of the load parameters, more often.

Later postings imply what I will say here: After every adjustment of your powder thrower, several charges should be thrown and discarded before throwing a charge for weighing. By "discarded" I don't mean to throw it away, just don't weigh it. Your measure (meaning the powder within it) needs to "settle in" throughout the powder pathway before consistent powder drops can be reliably thrown.

The "discarded" powder can be preserved for refilling the powder measure later. I don't recommend refilling the measure right away because opening and closing the cover will shake things up and settle the powder differently than normal operations will. Call me paranoid, but better safe than sorry. Some powders are more susceptible to this than others.

Good Luck,

Lost Sheep

 

[USSR]

I am sorry to say that USSR (post #2) is wrong when posting that there is zero relationship. There is a relationship. Unfortunately the relationship is not as tight as Richard Lee would have us believe.

Lost Sheep,

Please explain what relationship a powder measure with adjustment markings indicating the amount of powder it will throw, yet does not throw that amount of powder (and the degree of variance will vary from one powder measure to the next), has with the amount of powder it will throw? Are you talking about a +/- situation? When dealing with thousands of pounds of pressure right in front of our faces, "close enough" is not good enough when throwing charges, and you should NEVER base your charge weight on what a powder measure adjustment SAYS it will throw. That was the crux of my post, and I believe everyone took it as such.

Don

 

[mdi]

The key to using any powder measure is to do everything the same, every time. How fast you flip the lever, how hard you reach the stops, how often you bump the table when operating the measure, etc. You are allowing powder to drop into a cavity and fill it to a specific level that translates to your powder charge. If you do something to "settle" the powder in the cavity different than other fillings, the weight will vary, and it doesn't take much.

I'm not going to get in the "relationship" discussion above, but my Lee Powder Measure adjusting thimble is divided into ccs. So, just like a micrometer (thimble/vernier) I have an idea where to start for a given powder charge. My powder masure isn't a precision instrument, so the vernier/cc markings are just a guideline...

 

[KodiakBeer]

One might add that some powders are more consistent than others. Some of the stick powders for rifles need to be watched pretty carefully.

 

[kingmt]

Some good things already pointed out here. I do mostly as Lost Sheep said but want to add the less your measure gets bounced around the consistent it reads. This is true for me anyways. I haven't tried standing on one foot & taping with a ball ping yet.

When I first set my measure up I had to leave the nuts lose to allow it to work without jerking hard but after it got coated with graphite it worked fine. I don't have the cap on mine while loading or adjusting ether because I throw the first two throws back before measuring weight. If I make a mistake or get distracted while loading I throw it back. I don't know of anything this hurts but I'm sure someone will let us know if they don't think this is a good idea.

I also agree stick powder takes a little more attention.

 

[Bmac1949]

Asimpleman. I'm pretty new to reloading too but I can see that you have the right attitude by, when in doubt, seeking clarification before proceeding. Happy reloading

 

[ranger335v]

"does anyone know what I am doing wrong or trick/techniques "

Probably. For sure, it's unlikely your tools are creating a problem.

First, your measure's marked volume/capacity has some useful meaning but it's not a law; just adjust the measure until it drops the charge weight you want.

Next, no volume measuring tool can possibly drop fully repeatable weights with any solids. Small, fine powder kernels will measure great, large kernels will be less consistant; 4350 is a large tubular powder. So, if you want to be totally precise on each charge, get a trickler, drop slightly low charges and add powder until you get where you want to go. Always drop 2-3 charges without even bothering to weigh them after each measure change, just so things can settle down a bit.

Finally, no measuring tool can possibly work consistantly if the operator is inconsistant. Work the lever with the same smooth force and paced rythum each time and keep the powder column nearly the same. Do all that and your charge consistancy will greatly improve.

 

[Lost Sheep]

Greater than zero, less than adequate

I am sorry to say that USSR (post #2) is wrong when posting that there is zero relationship. There is a relationship. Unfortunately the relationship is not as tight as Richard Lee would have us believe.

Lost Sheep,

Please explain what relationship a powder measure with adjustment markings indicating the amount of powder it will throw, yet does not throw that amount of powder (and the degree of variance will vary from one powder measure to the next), has with the amount of powder it will throw? Are you talking about a +/- situation? When dealing with thousands of pounds of pressure right in front of our faces, "close enough" is not good enough when throwing charges, and you should NEVER base your charge weight on what a powder measure adjustment SAYS it will throw. That was the crux of my post, and I believe everyone took it as such.

Don

What mdi and ranger335v said. (Though I don't want to draw anybody into an argument, a clarifying debate is usually productive.)

All I mean is that the relationship between the markings and the actual amount of powder dropped is roughly proportional (which is less than absolute, but certainly more than zero, I think.)

When I had them, my RCBS powder measures would drop greater powder, the higher markings the thing was set at. Unfortunately, as you indicate, the repeatability of the thing was not good enough to rely on. A setting of 4.3 one day would drop a faily consistent amount of powder. If I changed the setting to 6.0 it would drop more powder. If I returned the setting to 4.3, it would drop less than when it was set at 6.0, but not necessarily the same as it had been dropping earlier at 4.3.

Thus, my assertion that there is a relationship greater than zero, but less than adequate.

I think we are in agreement in principle. Perhaps it is just the way I put it. I regret any offense given.

Lost Sheep

 

[ranger335v]

"I think we are in agreement in principle. Perhaps it is just the way I put it. I regret any offense given."

No offense taken, just a debate on the appearant problems the OP has experienced.

 

[Arkansas Paul]

One might add that some powders are more consistent than others. Some of the stick powders for rifles need to be watched pretty carefully.

This is correct. If I'm loading with H380, I can load as many rounds as I want and very rarely have to touch the measure. On the other hand if I'm loading with IMR4350 or IMR3031, I don't even use the measure. It's just a PITA. I weigh every charge with them and it's from a Lee dipper to the pan, then trickle to the correct weight.