July 22, 2019
By Charles E. Petty
Just when you think you’ve finally settled on the powder for the 9mm Luger, somebody comes along with a monkey wrench in the form of a new one. This time it is Winchester with a number that rang bells—until I figured out it wasn’t 571 of yesteryear.
Winchester 572 began at St. Marks Powder Co. as a shotgun powder for use in 20- and 28-gauge target loads, but as is often the case, it turned out to be a good pistol powder, too. As powder manufacturing methods have improved, it has become possible, and profitable, to define “niches”—powders designed for a specific cartridge or a family of cartridges. And Winchester 572 fit nicely into the 9mm and 38 Super niche.
Winchester 572 obviously carries the Winchester name, and once upon a time the St. Marks plant belonged to Winchester. The company sold the plant to General Dynamics and licensed Hodgdon to market powders under the Winchester name. Winchester owns the trademark for “Ball Powder,” so nobody else can use it, even if the product was made in the same place. Hodgdon uses “spherical” instead, and this has caused a little confusion.
The label on the new can says “shotshell” and then says, “Also fits a wide range of handgun calibers.” Actually, that is true for quite a few shotshell powders, but Winchester suggests that 572 would be especially nice in 9mm Luger and 38 Super. So that’s where we start, but the Hodgdon website also has data for quite a few other cartridges, and when time permits I’m going to try it in the 45 ACP.
The 38 Super is enjoying renewed popularity right now with shooters, but the major ammo companies have ignored it for decades. As a result, all the improvements in bullet design we’ve seen in the 9mm haven’t transferred to the Super. One point of contention has been the fact that the nominal bullet diameter for the 9mm is 0.355 inch, while the Super is 0.356 inch. For some shooters, this is a cause for great angst, but loading manuals often ignore it and show Super loads with 9mm bullets and vice-versa.
It is questionable whether one thousandth of an inch of diameter matters. And if so, how much? Does the difference have an effect on pressure? Well, probably but not much, and the handloader simply doesn’t have the equipment to find out anyhow. But the folks who publish loading manuals do, and that’s peachy.
Another factor that can confound handloaders is overall length. Loading manuals always tell us a number, but only one end of that equation matters. If a bullet is seated deeper than the length shown, pressures can go up—sometimes catastrophically. Conversely, seating the bullet out longer reduces pressures, although not as dramatically.
For that reason, I often seat bullets a bit longer than the published length, but there is no arbitrary number. When I begin seating a new bullet weight, I back off the seating stem a little and start seating a bullet. You can easily feel the resistance as it begins to expand the case. I go a bit and stop and look at the round and maybe measure length. When it looks about right, I try the plunk test. If it goes in the pistol barrel’s chamber easily but isn’t flush with the hood, the seating stem gets turned down a little and the test is repeated. The final step is to finish the crimp and then measure to see if the crimp changed the length and adjust if needed. Then I try it in a magazine; if it fits right, I’m done.
About now somebody is probably yelling at me about a crimp die. Some feel strongly that seating and crimping should be separate operations, and there is nothing wrong with doing it that way if you wish. But in several controlled tests, I have found no clear advantage to either method. Modern dies have a taper crimp built in, so, if nothing else, it saves a bit of time.
After this procedure, the overall length almost always ends up being five to ten thousandths longer than that shown in the manuals, and it has yet to cause me any problems. The lengths shown in the accompanying chart are derived that way, but I have a barrel, caliper, and magazine on the bench, too.
I shot the 38 Super a lot in my IPSC days and never once had a case of “super face,” where an overly enthusiastic load ruptured the case and blew gas and sometimes bits of brass all over the shooter. That’s one reason why we now have +P 38 Super brass and ramped barrels. In IPSC the 38 Super could make the major power factor—something the 9mm couldn’t do.
Today’s handloader has a variety of choices in powder available for almost any cartridge he loads. That can be both blessing and curse. Way back when, there might only be a couple of powders suitable for a cartridge, but now there can be as many as a dozen that might be used. It’s up to us to find out which powder best meets our needs. I tend to think of them as niche products, and manufacturers now have the ability to tailor burning rate and density to favor a single cartridge—or a small family of cartridges with similar needs.
While we characterize powders as single or double base depending on whether nitroglycerine is used, there are chemicals and processes that are used to stabilize the chemistry, suppress flash, modify burning rates, and control the porosity of the powder grains that give powder makers considerable flexibility to fit rather narrow niches.
The powder burning rate charts found in most manuals can give us some clues. The numbers do not have specific values. Instead they are relative for comparative purposes, from faster to slower based on their position in the chart. So if we know a certain powder is good with one we already load, another powder close to it on the chart may be, too. But we cannot use data from a powder we know to extrapolate to the new one. We already know the folly of apples-to-oranges comparisons, and this is another example.
The 38 Super is the stepchild of the 38 ACP (a.k.a. 38 Auto, 38 Colt Automatic) from 1902. Introduced in 1929, the intent was to add some horsepower to the 38 ACP by increasing the allowable chamber pressure. The customary 130-grain FMJ went from 1,040 fps to 1,215 fps. The cases of the ACP and the Super are exactly the same, and for reasons perhaps known only to Mr. Browning, they follow in the footsteps of the 32 ACP and are of semirimmed design.
The original barrels had a shelf inside the hood (headspace extension) that caught the semirim to establish the headspace. This was thought to be responsible for the rather lackluster accuracy of early 38 Super pistols, so when IPSC shooters began to face targets at 50 yards or more, it was changed to headspace on the case mouth as was the situation with most semiautomatics. Then shooters attempting to make major power factors with lighter bullets began to experience ruptured cases due to excessive pressure, so the web was thickened and +P was added to the nomenclature of the Super.
The latest burning rate chart puts Winchester 572 between Accurate No. 5 and HS-6 and just a tad slower than AutoComp and CFE Pistol. Accurate No. 5 used to be my favorite for the 38 Super, and both CFE and AutoComp have done exceptionally well in 9mm.
Putting Winchester 572 to a Test
Anytime a new powder is announced, magazines will be swamped the next day with requests for loading data they don’t have. And even if they did have the powder, it takes awhile to load and test ammo and sometimes months before it gets to print. This time things were different. When I received this assignment, Hodgdon already had data on its website. When the powder arrived, I went to work.
My practice is to study the data and establish three charge weights to test. I used Hodgdon’s established starting and maximum loads, and then I picked a charge in the middle for the third. When companies are generating data, most of them work up to the maximum charge in a pressure test gun and then choose an arbitrary reduction (usually 10 to 20 percent) for the starting load. They assume that charge will function in most pistols—and it usually does—but the 38 Super pistol I used here was new and tight, so a couple of the starting loads did not function (DNF). It is also possible to work down from that point in search of less recoil or better accuracy, but do it in small steps to avoid sticking a bullet in the bore.
Projects like this require a lot of time loading, shooting, chronographing, and measuring, so anything that speeds up the process is a bonus for me. Enter the LabRadar chronograph. It uses nothing downrange, which greatly simplifies set up, and it is unaffected by ambient light. The unit sits on the bench beside the gun and tracks the bullet by way of Doppler radar. When the unit is placed even with the muzzle of the gun, it is triggered by the sound of the shot, and the display shows “V0,” which is the actual muzzle velocity. It will also display five additional velocities at specified distances.
Conventional chronographs really give us the velocity at the midpoint of the screen spacing. So that is 2 feet, and the first screen is 10 feet from the muzzle, so the display tells us the velocity at 11 feet. For most purposes that small discrepancy is ignored.
The heart and soul of the unit is surely the computer program, and the most daunting part is, with the instruction manual on your lap, inputting all the variables. For the most part, one can establish standard distances and use them all the time. Then the only thing you need to change is bullet weight. It records all the data and saves it automatically to an SD card, but old habits die hard, and the data was also recorded on the spreadsheet I made with all the loading data.
The LabRadar saves an incredible amount of time because set up is so simple. Position the unit even with the muzzle, 10 to 12 inches to either side, and there’s a small notch on top of the unit that you simply align with the target. Then you can start shooting. When you finish a string, push one button and the display gives you the average, extreme spread, and standard deviation on one screen.
Winchester 572 is a little fluffier than many spherical powders, and most charges come close to 100 percent loading density. In other words, they don’t leave much empty space, and some are lightly compressed. That is usually a good thing.
As often as possible, I used the same bullets the Hodgdon technicians did and found very good agreement between their velocities and mine. But the most striking observation was the consistent accuracy among the different charge weights. There is usually a “sweet spot” for accuracy, but with most of the bullets tested, the differences between start and maximum charge were small. While the data speaks for itself, the Speer 90-grain Gold Dot averaged 0.623 inch for all nine groups.
Everyone wants to know about cleanliness. When the test started, the guns were cleaned and received no attention during the test other than a drop or two of oil. When the guns got home from the shooting range, neither bore showed any visible signs of fouling, and a new patch that was run through the 9mm barrel after 315 rounds using nothing but Winchester 572 was only lightly soiled when it came out. Had there been any cast bullets with conventional lube in the test, that result would surely have been different. But it’s clear that Winchester 572 is clean.
To view Winchester 572 Load Data for 9mm and 38 Super, click here.