Cons: Limits on its practicality
As with many things, devotees of certain "sporting" activities can develop near religious faith in the equipment they use, the manufacturers that produce them, and the 'celebrity' experts who provide endorsements. There is no reason to apologize, for we all tend to imprint on a method, tool, technique, or "way of doing things" when an activity grabs our attention. It all comes back to something about 'first impressions' or 'first loves' or 'first successes.' So powerful can this imprinting be, it is sometimes easier to get one to change their religion than change, or even take an objective look at, such things.
Given that 'dipping' powder is a very traditional method of measuring charges in reloading, I would normally be one of the first in line and loudest of voice for adherence to TRADITION. Given that the Lee Powder Measure Kit has been around for over 40 years, it would be impossible to argue that it is a tool that doesn't work; at least to a degree for the price paid. Given that there are many who would see any criticism (real or perceived) of this method/tool as "blasphemy," there is an intrinsic 'risk' in attempting an objective analysis of the product.
So, why do a review?
What Is Powder Dipping?
It was that long ago that mechanical powder measures were not only unreliable in terms of accuracy, they were either nonexistent or unattainable; which can be, effectively, the same thing. Coming out of the tradition of black powder firearms, 'dipping' some sort of container into a batch of powder and pouring the dipper's contents into a cartridge case was not only traditional, it was pretty much the only way many reloaders could get a relatively consistent charge into the process of creating usable ammunition. The trouble was that dippers made for black powder were unsuitable for smokeless powder measuring.
Even today, 'dippers' will use various 'tools' to scoop charges. Some use teaspoons. A few use various forms of plastic 'containers;' though you must be very, very careful, for some plastics will create a static charge - static charges and gun powder being a somewhat volatile combination. Any number create their own dippers out of various materials; including cartridge cases. The crux is to have something that will, given proper technique, create consistent charges from 'scoop' to 'scoop.'
Proponents of this method will often point to consistency in 'measured' charges being a significant factor in their advocacy. However, safety is usually the most often cited, major criterion. Or, as Lee states: "In the 44 years of selling reloading tools with smokeless powder dippers, we have never heard of an accident because of an overcharge of the powder specified... Dippers are inherently safe. They have fixed capacity that cannot get out of adjustment... Even if you grossly misuse a dipper by heaping it, the charge will be only 7 to 12 percent too much. The percentage depends upon the powder type. If you started 10% under maximum, you are probably safe eith a modestly heaped charge." - Richard Lee, Modern Reloading, 2nd Edition, 2003, reprint 2007, pg. 90
Sounds Good, But...
Powder dipping is not the same as "weighing" charges. Note that Lee refers to capacity and heaping. Powder dipping is a measurement by volume. While a valid methodology, it has some inherent problems which can lead to inaccuracies and/or inconsistencies. First, powder density can change from lot to lot (production runs) and 'brand' (e.g., Hodgdon 4895 is not exactly the same as IMR 4895), be impacted by humidity, vary based on the dipper's technique, etc. Second, the volume capacity of a given container changes based on the type (structure) of material placed therein. In this case, ball powder can be packed more densely into a dipper than can an extruded powder. Finally, as applies specifically to the Lee dippers, conversion of assumed volume, with the potential +/- deviations, to weight is not an 'exact' arithmetic function.
Why would one want to convert volume to weight? After all, Lee claims: "By using the same dipper for every bullet weight, and changing the powder to a proper quickness so pressures will remain in the safe range, you are maintaining the same loading density. If the load density is near the practical limit of the case capacity, the loads are less sensitive to slight variations and produce best accuracy with minimum effort." - Richard Lee, Modern Reloading, 2nd Edition, 2003, reprint 2007, pg. 91
Sounds good. As Lee also pointed out immediately preceding this quote:
"Dean always felt no one could dip a charge quite as precisely as he. He would, and I have little doubt that he still does [Dean Grennell passed away in, I believe, 2004], use a special technique. He pushed the dipper bottom first into the powder and let the powder flow into the mouth of the dipper. Then striker it off with one of his business cards and consistently get charge uniformity of 1/10 grain." - Richard Lee, Modern Reloading, 2nd Edition, 2003, reprint 2007, pg. 91
As a noted gun author, Dean Grennell was a "guru" for at least a couple generations of reloaders. He was also, probably, the loudest of the proponents of the Lee dipper system...
Alright, alright. What does this have to do with the question: "Why would one want to convert volume to weight?"
As Lee points out in the paragraph immediately preceding this last quote:
"...I remember the good old days, when Dean Grennell and I used to shoot on the back forty. It was early in Dean's writing career and early in my manufacturing career. Dean would get early production model guns for evaluation...We developed loads for the then new calibers...We always loaded by volume, using a Lee dipper kit. We would work up suitable loads by watching for signs of pressure and check velocity with my Herters' counter chronograph. Dean would then go home and weigh the charges on his scale to report to his readers how many grains of powder to use for the different bullet weights and the resulting velocities. This was done because charges in grains of powder are the accepted standard method of reporting load data. [emphasis mine] Yet, all test rounds were loaded by by volume using dippers or combinations of dippers on the range. The point of this little anecdote is - we have a great deal of confidence in measuring powder with the Lee dippers. " - Richard Lee, Modern Reloading, 2nd Edition, 2003, reprint 2007, pg. 91
This is a crucial point. Virtually every reloading manual lists load data based on grain weight; with a number including an associated column for each load identifying the % capacity for that particular grain weight for the specific test case used. (Case capacity does vary from manufacturer to manufacturer and can vary from product line to product from the same manufacturer.) Thus, the point of reference that the vast majority of reloaders have is based on charge weight and not a measurement of volume; and, significantly, not a measure of volume based on a specific manufacturer's tool. The reason being that grain weight is a consistently repeatable number; i.e., assuming proper functioning, a Lyman scale will read the same weight as an RCBS scale, as a Hornady scale, etc. It is not as susceptible to issues such as density, improper technique, or the specific tool used.
Maybe Lee summed it up best:
"Powder dippers are the time-proven, safest way to reload ammunition, provided charges are kept 10% under maximum. Because powder density can vary by as much as 16%, you may frequently be reducing your charge by considerably more than 10% with the dipper. The only way to be positive of charge weight is with a powder scale. [emphasis mine]" - Slide rule from Lee Powder Measure Kit w/ instructions, showing powder charge for each dipper in the kit
Why All The Lead-In?
Why all the background on "dipping?" Let's just say it makes what follows easier to understand.
At an average cost of approximately $10, the Lee Improved Powder Measure Kit contains 15, yellow, plastic scoops or 'dippers.' These are sized based on volume in cubic centimeters (cc), in .3 cc increments from .3 cc - 4.3 cc. Each dipper is embossed with the size and a warning to "Use Only With Lee Charge Table." This charge table is included in the form of a 'slide rule' which contains instructions and allows for conversion of the volume 'dip' for each of the 15 dippers to grain weight the 95 listed powders; coming out to 1,300 different loads. (If you lose or damage this slide rule, a 2 page table with the same listings can be found toward the back of Richard Lee, Modern Reloading, 2nd Edition (2003, reprint 2007).
That's it. That's the kit. So... Why all the lead-in?
Well, now that you know the theory behind them and how you're supposed to use them, I can now more fully expand on why, from a practical standpoint, you will need to get a good scale (a specific dipper comes with each set of Lee dies and the Lee Loader - see The Classic Lee Loader: Nearly As Useful As The .30-06 Itself For Tyro Or Pro), even if you primarily rely on the dipping method and save the expense of a more sophisticated powder measure. (Even the more sophisticated powder measures are based on volume. However, they are typically set based on having measured, on a scale, the specific grain weight for the charge you want. While they too will have some variation, they are 'mechanically' consistent - something not always achievable with the dippers - and are always, or should always be, spot checked [using a scale] throughout a loading session to ensure consistency of the powder thrown.)
Let me stipulate that one can develop a certain level of consistency in measuring a charge using these dippers; assuming that you can live with the slight variations already discussed. Also, let us recognize that there is a certain safety factor in that the dippers are, in a sense, undersized. But, it is these very factors that make them somewhat impractical for all but the occasional reloader that only wants to put together a few consistent, but, perhaps, less than ideal loads.
Without going through a litany of exemplars, let's take just one situation to illustrate the problem. Next to the .22 and the .30-30, perhaps the most popular hunting cartridge in North America is the .30-06. A very popular and ubiquitously useful powder for this and a plethora of other cartridges is IMR 4064. A solid, practical "Pet Load" in this caliber for hunting is a 165 grain bullet pushed by 48 grains of IMR 4064.
The dipper that comes with the Lee Loader for .30-06 is the 3.4 cc, so we'll use this as our reference point. According to the slide rule that comes with the kit, the 3.4 cc dipper will measure a volume of IMR 4064 equivalent to 45.6 grains. That's 2.4 grains short of the "Pet Load." That's approximately 5 % short and doesn't allow for the 'slight variations' from density or technique. In fact, most users will cite these variations ranging from Grennell's 1/10 of a grain to as much as 2 grains. Thus, if we split the difference, using the 3.4 cc dipper means that you could average as much as 3 grains less than the "ideal" load you were striving for - something that you would not know or be able to accurately measure without a scale.
The next dipper size, 3.7 cc, scoops a theoretical 49.7 grains of IMR 4064. In fact, no combination of dippers comes out to 48 grains. In the specific case of the 48 grain loading, in theory, you could use the .3 cc dipper to dip 4 grains of IMR 4064 and repeat 12 times to achieve the correct loading. Unfortunately, that assumes an exact dip, each time, with no variation. Sounds a trifle cumbersome.
Why does this matter? Do you need to be that exact?
Unless you are willing to use only those loads which the dippers are intrinsically capable of measuring, plus or minus a certain variation, you're going to have to find a way to tweak the loads. This gets us into issues of safety (underloading can cause problems just as overcharging can lead to real issues) and suitability. If you're just looking for plinking loads that go "BANG" and let you shoot, then loads toward the middle of the range for a given bullet weight in a given cartridge will work; which is exactly what these dippers were designed to do. But, when working up loads that hit the "sweet spot" for any given firearm, that load with the best accuracy for that weapon, most will load a series of rounds in increments of from 1/10th to 2/10th's of a grain.
Such precision is obviously unattainable with these dippers if your starting reference point is grain weight. Remember, Grennell ignored weight and simply played with the volume to determine the proper loading for a given firearm - then measured the grain weight to be able to communicate a starting point for people to begin working up a load for their, specific weapon. This is the point of the whole discussion and the limit to the functionality of the Lee Improved Powder Measure Kit.
Is It Worth The 10 Bucks?
If you don't have room or the budget for a good powder measure (and the good ones can be $100 or more), then the traditional method of dipping powder is still viable as a starting point. If you just want ammo that will go "BANG" with a certain consistency, then you can use these dippers to that end. If you want or need more precision, then these dippers must be used in conjunction with a quality scale. You simply use the dipper to 'throw' your initial load into the pan, then use a powder trickler, a teaspoon, or another, smaller dipper to jigger in what you need. (A trickler is the best in this sense, in that it allows for the addition of powder a single kernal at a time.)
Eventually, most people graduate to a 'faster' means of measuring powder. But, there are cartridges where the dippers can produce loads that are "good enough" for the purposes intended. (In fact, this is the powder measuring 'system' that was being used by Liam Neeson in the movie Next of Kin long before he took up a lightsaber as a more "elegant weapon.") Even with all this verbage, don't think that I'm saying it doesn't work.
In truth, this kit, in one form or another, has been working for many for over four decades. You will still hear a devoted few that will claim that nothing else is as reliable or useful. What I am saying is that you have to be aware that this system has its inherent limitations. The only way to mitigate those limitations, not to mention effectively using the vast majority of the reference materials available vis a vis reloading, is to utilize these dippers in conjunction with a good scale.
But, hey. What d'ya want for 10 bucks?