As I discussed in September/October, shotgunners have a hard time determining the quality of lead shot. This is because there are no worldwide standards for lead-shot quality: no universal rating system for roundness, no universal standards for pellet-to-pellet uniformity, and no standards for either the amount of antimony added to make lead shot hard or the language used to describe the hardness obtained.
In this hodgepodge, buyer-beware marketplace, shotgunners are left to figure out things on their own. In my experience most do relatively nothing to determine the quality of the lead shot in the loads they are buying or the shot they intend to reload. Many succumb to the theory that if shot looks good, it must be good. And as you will see, that can be a hugely erroneous assumption.
Let’s say that you don’t want to theorize but want to really know what lead-shot hardness is. Various crush tests are used by industries throughout the world to test the hardness of metals. One crush methodology that can be applied to shotshell pellets is the Diamond Pyramid Hardness test. It is used to determine and express the hardness of steel shot and other hard pellet types. But it doesn’t work for soft pellets like lead shot. What to do?
One alternative is to pay for laboratory qualitative analyses to chemically determine the actual antimony levels in samples of lead shot, but this is prohibitively expensive. So years ago I decided to test shot hardness mechanically to determine relative rather than actual hardness. With the assistance of an avid shotgunner—the late Phil Johnson of Merced, California—I put together a simple and inexpensive device using a crush methodology similar to the Diamond Pyramid Hardness system because none are available commercially. The component parts of that device and instructions on how to use it were described in my column in September/October 2004 (“A Reloading Primer: Shot Testing”).
Armed with a dial caliper and a crush-test device similar to the Johnson/Roster design, anyone can obtain an accurate idea of the quality of the lead shot in their factory loads or in bagged shot sold for reloading. The use of both devices takes all the mystery out of it, and with them I periodically conduct rather exhaustive series of lead-shot quality tests.
The Latest Tests
During January and February 2010, two research assistants and I spent a total of 480 man-hours (three people, eight hours a day, for 20 days) conducting pellet-count, charge-weight, shot-hardness and pattern tests on 36 different lead-shot pellet types. The tested shot included American and imported, as well as bagged shot sold for reloading. We tested 25 different factory loads and 11 different brands of bagged lead shot sold for reloading in the US. The testing included three lead-shot types: black, so-called copper-plated, and nickel-plated.
Ten-pellet samples from each of the 36 loads were measured with a dial caliper for actual diameter and roundness. Ten-pellet samples also were tested for relative hardness using the Johnson/Roster crush-test device. Pattern tests were conducted in five-round samples through two different chokes at two or three distance increments for 13 of the 36 samples.
This took a lot of time—and labor is not cheap these days—but this kind of thorough testing yields 95-percent confidence levels in the results obtained. It also brings shotgunners, wildlife agencies and me up to date on the quality of lead shot being sold in the US.
Now some realities. First, a large pellet is inherently more resistant to deformation than a small pellet, and that’s why no manufacturer I am aware of adds as much antimony to, say, its No. 2s as it does to its No. 8s. So when making a relative-hardness comparison via a crush test, to glean an accurate idea of the difference in hardness between two brands one cannot compare the degree of crush measured for a large pellet of Brand X to that measured for a small pellet of Brand X, Brand Y, or any other brand. Instead, whenever possible, the same pellet sizes should be compared between brands. And then from those results one must be careful to realize that accurate generalizations to all shot sizes in both brands cannot be made.
Second, here is the methodology for a soft-pellet crush test: 1) Measure each pellet’s before-crush diameter with a micrometer, 2) drop the crush-device rod a given distance onto the pellet placed on an anvil, in this case a flat one, 3) mic the after-crush diameter, record it and compute the difference, 4) do this for a sample of at least 10 pellets selected at random from the same shell or bag of shot, 5) calculate the percent change between the average of the before versus after diameters to express the relative degree of hardness. The larger the percentage of change, the greater the relative softness of the pellet.
We measured three brands of unplated lead shot sold for reloading in sizes No. 7½ and 8: West Coast Premium Magnum Extra Hard, Remington STS Magnum Grade 6-percent Antimony, and Lawrence Brand Magnum Shot. For comparison purposes, let’s look at the results for No. 8s.
All three bagged-shot brands measured close to the perfect diameter for a US No. 8 (.090"), but the Remington STS product’s crush value was only 33.3 percent—versus 39.1 percent for the West Coast Premium’s and 39.3 percent for the Lawrence Brand Magnum’s. Comments: The Remington No. 8s were the truest to diameter, averaging exactly .090", and also the hardest, although all three products were close in hardness and quite uniform in diameter.
We measured five brands of plated lead shot sold for reloading in sizes BB through No. 6: Aquila Nickel Plated (Italian-made), Lawrence Brand Copper Plated, Winchester Lubaloy (copper plated), Precision Reloading Nickel Plated, and Ballistic Products Nickel Plated (Italian-made.) For comparison purposes, let’s look at several of these in size No. 6, with West Coast Premium Extra Hard (unplated or black) lead shot in No. 6 as a control.
For trueness to diameter, Precision Reloading Nickel Plated No. 6s and West Coast Premium Extra Hard (black) No. 6s came out the best, averaging .111"—very near a perfect US No. 6 (.110"). The other products deviated by as much as a full pellet size from the US standard. Lawrence Brand Copper Plated No. 6s measured .113"—closer to a US No. 5-1/2. One of two batches of Ballistic Products Nickel Plated No. 6s averaged .102", making them US No. 7s, with the other averaging .1035", making them US No. 6-1/2s. Of these four No. 6 pellet products, the Ballistic Products Nickel Plated 6s, although measuring smaller in diameter than marked using the US shot-size standards, tested the most uniform in diameter and had the cosmetically “best-looking” plates.
The Precision Reloading Nickel Plated No. 6s tested the hardest of the group, with a percent-change crush value of 19.8 percent. The Lawrence Copper Plated No. 6s and West Coast Premium Extra Hard Lead (black) No. 6s measured only slightly softer at 21.2 percent and 21.6 percent, respectively. The Ballistic Products Nickel Plated No. 6s—both batches—turned in percent-change crush values of 32.4 percent and 35.6 percent, respectively, meaning that they were significantly softer than the other No. 6 pellets tested.
If we look at the now-discontinued Winchester Lubaloy line, which consistently tested the hardest and patterned the best of any lead shot I’ve tested over the years, Lubaloy No. 5s turned in a very nice .119" average diameter with a 19.3-percent-change crush value. (I never used or had any No. 6s to test.)
One overall truism becomes apparent from these reloading-shot test results: If you buy plated lead shot because you assume it’s harder than black lead shot, think again. From a statistical standpoint, none of the plated shot products in size No. 6 tested significantly harder than the unplated West Coast Premium Extra Hard Lead. And our testing found significant relative-hardness differences among the plated-lead-shot products—the No. 6s being just one example. These data suggest a cautious and objective approach is needed to obtain the best shot for the money and intended purpose.
Next time I’ll describe patterning results, with a brief foray into CONSEP’s (Cooperative North American Shotgunning Education Program’s) terminal-ballistics findings. Besides looking at pattern-test results for factory lead loads and the bagged shot discussed above, I will examine in detail the quality results for factory-loaded lead shot.
To correspond with Tom Roster or to order his reloading manual on buffered lead and bismuth shotshells, his HEVI-Shot reloading manual, his updated 75-page Shotgun Barrel Modification Manual or his instructional shooting DVDs, contact Tom Roster, 1190 Lynnewood Blvd., Klamath Falls, OR 97601; 541-884-2974; firstname.lastname@example.org.
- By: Tom Roster