Harrell Powder measure

[stubbicatt]

Fellas, I purchased one of these. I have been somewhat surprised at its variations in powder charge. Now, in fairness to the measure, I haven't mastered a uniform stroke, which may have some bearing on its performance.

The instructions say not to "knock" the measure at either end of the stroke, and that's fine.

I figger I'll take my time and arrive at a stroke that is consistent, but I wonder if any of you has a suggestion based on experience on how to use this?

[Unclenick]

No idea what powder you are using? Coarse stick powders are difficult for most measures. I'm sure you'll find fine stick and, especially, spherical powders do well in your Harrell. For a more consistent "knock" on the measure, you can use heavy rubber bands to strap a small door knocker to the powder reservoir and let it drop once for each throw. Some folks use rubber bands to hold a fish tank pump onto the measure and use a button to give it a second of vibration for each throw.

A round reservoir bottle can be cut open at the bottom and extra baffles inserted to keep powder column weight more uniform. I have a PDF file of powder baffle templates and instruction at my file repository.

There are only two measures I've tested personally that can stay within 0.2 grains with medium to coarse stick powders. One is the JDS Quick Measure, which is a very nice tool designed specifically for stick powder metering, but it takes more fiddling to set up than a micrometer adjusted type like yours. It has to be done with an optional dial indicator gauge if you want that level of repeatability. Its small charge adapters for pistol can jam up with some fine propellants (Power Pistol, for example), so your Harrell will do better there.

The other successful stick measure is one of my two Lee Perfect measures, and it will throw that well most of the time except for IMR4064 where 0.3 grains precision is more typical with it. The other Perfect I have won't hold that well. I think that's because its wiper is defective and catches on grains much more frequently. On the other hand, the Quick Measure cost me what four or five Perfects would by the time I got all the accessories a wanted with it.

[PA-Joe]

You have to master the double tap. Double tap on both the up and down strokes. It also helps if you put a baffle in the powder tube so that there is a uniform load going into the measure.

[mehavey]

I've got two of them: the Schutzen and the Classic Culver. They are absolute gems.

But as good as they are, it's the uniformity of both the powder column density and the settling "taps" at stroke's top & bottom. I can keep it +/- 0.1 absolute with ball easily. 'Purty much' that with flake, and "close" to that (say an SD=0.01) using extruded.

That SD means what it says.

[Unclenick]

An SD of .01 grains would mean (assuming normal distribution) 68.3% of your charges are within a hundredth (0.01) of grain of one another, and 95.4% are within two hundredths (.02) grain, and 99.7% are within three hundredths (.03) grain. That's well beyond the ability of any dispenser I have or of my scales to be able to verify it. I understand the Prometheus weighing dispenser is supposed to be able to get to about that, though.

[PA-Joe]

Does that measure come with both a rifle and pistol rotor? Are you trying to do pistol or rifle.

[mehavey]

Would you believe the author meant to type "1/10th" (0.1) grain?
-1 for attention to obvious detail.

In any case, while I can keep things +/- an absolute 1/10th grain with ball and flake, extruded powders turn that "1/10th" into a more widely spread distribution whose std deviation is that same 1/10th grain.

Uncle Nick knows what I mean.

[stubbicatt]

... to measure TAC powder. TAC is a ball powder. I am convinced that it must be my technique, but I'm not getting +/- .1gr by any shakes.

I tried to lift the lever to the top of the stroke, and pause long enough for the charge to enter the rotor, and then smoothly lower the lever. I attempted to do this in a way that did not tap at the top or at the bottom of the stroke, as the instructions suggest that tapping is not a good thing to do.

As it is, I think I paid a premium for a measure which does not do any better than a Redding, although it sure is a nice piece of worksmanship.

Perhaps it needs to break in or perhaps I just need to refine my technique.

[PA-Joe]

Pausing does not help. You need the baffle and you have to tap or bump the lever several times to get the powder to compact a little into the rotor.

[Unclenick]

Were there any instructions to clean the thing before using it? Any trace of oil will mess up measuring badly.

Most measures don't do their best straight out of the box. They need time to get a coating of graphite or other lubricant from powder before they do. Some folks just run two or three hoppers full of a graphite coated powder through to get that. I don't like moving the powder around unnecessarily, so I put a half cup of graphite in the hopper, shake it to get a coating for anti-stat purposes, then run the graphite through the measure a couple or three times with the chamber set on maximum size, then once more through with it set on minimum size.

Once it is clean and graphite coated, it usually only takes a couple dozen charges of powder for it to settle.

[brickeyee]

A baffle helps a lot.

After filling the hopper you need to meter a decent number of charges to get everything settled uniformly, and on a new measure run a lot of powder through (like at least a pound) to coat everything with graphite from the powder.

I do not know of anyone who does not tap top and bottom.

It is far easier to simply resign yourself to the tap than to try and not have the touching stop the chamber movement.

[stubbicatt]

OK. The opening into the measure cavity has a small orifice, is this not a baffle?

I do not see how one can put a baffle inside the powder bottle which came with the measure, as it is a "bottle neck", and at the other end is a small opening into which one could add additional powder, which has a plastic plug near as I can tell to keep it from spilling when you remove it from the powder measure body to empty it.

I do not see how one could insert a baffle in there?

Does the small orifice serve as a baffle?

[mehavey]

You are correct, the HARRELLS measures use a soft plastic (very convenient) bottle to feed the powder. It will not take (and does not need) a baffle.

Try this:

- Keep the bottle at least half full.
- Sharply tap the bottle low down a half-dozen or so sharp taps to settle the powder at start.
- Dispense a half-dozen loads (pouring them back into the bottle top/bottem) even before adjusting for exact load
- When actually using...

A. Snap the level-arm up sharply and contact the stop firmly. [ SNACK ! ] This ensures powder drops/settles cleanly/consistently into the measure's powder chamber

B. Snap the level-arm down sharply and contact the stop firmly again [SNICK ! ] This ensures powder drops cleanly into case . (Both the SNICK and SNACK also gently/continuously vibrate/settle the powder in the plastic bottle as you proceed w/ loading multiple cases)

D. Develop an easy rhythm: pick up new case -SNACK! - [pause] - SNICK! - put down case - pick up new case -SNACK! - [pause] -SNICK! - put down case - pick up new case -SNACK! -[pause] - SNICK! ... you get the picture.

TAC, being a ball powder, does very well.

[Unclenick]

But Harrel recommends not tapping and he is not getting good dispensing. It suggests a hang-up somewhere. With a spherical he really should be holding a tenth pretty easily.

I'll ask again, were there any instructions suggesting cleaning before use? Lots of lubricants are used during machining, and if any were left in place, they can easily cause inconsistency. I would call Harrell and ask about that possibility and for other suggestions? 540-380-2683.

Once you know it is free of oil, again, running graphite or a lot of powder through it will lubricate the tool and rid you of static cling.

Because the powder bottle has a standard threaded round ID mouth, you can empty the bottle and put a baffle into the mouth, put the bottle in the measure, then add powder through a funnel in the top. Yes, the corners of the baffle will stick up into the bottle, but it still interrupts changes in powder weight above it, so it will still add an extra layer of flow smoothing into the mix. Can't hurt.

[mehavey]

In the Harrells, I've only seen static cling (slightly) in the clear plastic drop tube -- and even then it was minor "suspended" grains dancing inside. A couple of wipes on the tube with the throwaway anti-static cloth that you normally throw in the dryer with your clothes solved that issue right off.

As far as the possibiity of an oil film in the metallic works themselves, that should show up when you turn the measure upside down to empty the powder back into the plastic bottle before removing it altogther. Do you have noticeable powder remaining/clinging in the cavity when you look into it afterwards? (I haven't noticed anything unusual myself.)

Running ball powder through the machine is akin to running a graphite medium. It should benefit things fairly quickly

As far as the "Snick/Snack" routine suggested above, we're not talking about taking it to extremes. Merely a deliberate "stop" as both top and bottom. In both the measures I have, I've found that it evens things out.

[tswelsh]

I like the idea of tapping at the top a couple of times to get the powder to settle into the reservoir and will try it.

I got the Harrell Schuetzen a few months ago and find it much more accurate than the RCBS that came with the kit. I ran 150 through it this weekend alternating Bullseye and Vihtavouri during this batch and found that 90% of the time the weight is right on. There were 2 or 3 times during the batch where I just couldn't get the full charge I was looking for even after 4 or 5 in a row and would have to adjust. In every case I was coming in under which tells me that more than likely, a clump developed somewhere that wouldn't shake loose.

Getting the Harrell reduced my frustration considerably. Between the all brass construction, glass drop tube and smaller plastic reservoir, I find it much more enjoyable.

[Unclenick]

Welcome to the forum.

I have to ask, because a lot of newbies do it: did you realize you were reviving an almost two year-old thread? You'll find that often the folks in the old discussion aren't any longer paying attention, so you may get no further feedback.

To your point, though, I'll add that some folks actually use heavy rubber bands to hang a fish tank aerator pump on the side of the powder hopper, then have a momentary switch rigged to power it up to buzz it for a second to settle the powder between throws. I find with stick powders that too much settling makes it hard to dispense (you cut more grains), so the application has to be judicious. It might be that Lyman's built-in door knocker approach is a better compromise (see it on the front of a #55 measure). The idea is that makes it easier to repeat the strength of the tap more easily. You could accomplish the same thing just by snapping a rubber band around the hopper if you are careful to pull it out the same amount each time.

[impalacustom]

oops sorry for the necro - deleted comment

[totaldla]

Joe at Realguns did an exhaustive review of powder dispensers that everyone should read before buying one.

And the sad news is that the $60 Uniflow performed as well as the $268+ Harrell.

Harrell versus Uniflow