Understanding Ammo Dimensions Can Prove Economical To Beginning Reloaders.
While in the process of helping a friend’s widow sell his reloading gear a potential buyer said this, “I want a set of dies that will only load .38 Specials because I already have .357 Magnum dies.” That’s not exactly how things work. A set of dies for loading a shorter straight walled case will always work for loading a longer straight walled case of the same dimensions.
For example, a set of .38 Long Colt dies can be adjusted to load .38 Specials and .357 Magnums. A set of .38 Special dies can also load .357 Magnums but a set of dies marked only .357 Magnum will not serve for the shorter rounds. Why? Because a seating/crimping die marked for .357 Magnum can’t be turned far enough into the reloading press to crimp on shorter .38 Specials. The die bottom hits the shell holder before the crimping shelf in the die will contact .38 Special case mouths. The same may possibly be true for case mouth belling dies marked only “.357 Magnum.” Resizing dies so marked do work just fine for the shorter cases.
Just for information here are the case lengths for .38 Long Colt, .38 Special, and .357 Magnum in the same order: 1.03 inches, 1.16 inches and 1.29 inches. Shell holders and bullet diameters are the same for all three. Here are three more examples: .44 Russian, .44 Special and .44 Magnum in the same order are 0.97 inch, 1.16 inches and 1.29 inches. Again dies marked for the shortest case will work for all three, dies marked .44 Special will work for .44 Magnum but ones marked for the magnum length cases will only be suitable for it. And repeating myself again, shell holders and bullet diameters are the same.
Sometimes there are minor details, which must be addressed. Take .45 S&W “Schofield” and .45 Colt for example. Dies for the former round can be used for loading the latter with proper adjustment and both cartridges can use the same bullets. However, shell holders for the two cartridges are different because .45 S&W case rims are about 0.010 inch wider than .45 Colt rims.
The same is true of straight walled rifle cases. When jumping into black-powder cartridge reloading I already had .45-70 reloading dies. So when a .45-90 was acquired all that was necessary was to turn my .45-70 dies 0.30 inch up in the press, which instantly transformed them into .45-90 dies. Case lengths for those two cartridges are 2.10 and 2.40 inches and case head dimensions are exactly the same. Then I bought a rifle chambered for .45-100, which has a 2.60-inch case and same case head. Thinking I had it made with the .45-70 dies they were turned up in the press and I ran into trouble. The die bodies were too short so their threaded portions ran out before they could be adjusted high enough. By that time I had also acquired .45-90 dies and being a bit longer they worked fine when adjusted for the 2.60-inch .45-100 case.
In the realm of bottleneck rifle dies there is less versatility but still some items will work for several cartridges. Let’s take .222 Remington neck-sizing dies for first example. That particular neck-sizing die will serve for .223 Remington and .222 Remington Magnum. Of course the die must be adjusted properly in the press for each case length.
Neck-sizing dies for .308 Winchester will work for .30-40 Krag and .30-06 but not for the longer .300 Magnum cartridges. The width of a .308 case at the beginning of its shoulder is nominally 0.454 inch. Cases for .30-06 are nominally 0.441 inch at that point so they will fit and .30-40 Krag dimension there is only 0.419 inch. However, the various .300 magnum rounds are much larger at that point: ranging from 0.490 inch up. (Except .300 H&H) There is one important caveat with bottleneck cases and neck sizing dies. They must be carefully adjusted so that case shoulders are not set back. Doing so will create the same condition as excess headspace.
How do you avoid setting back the case shoulder? Lubricate a case neck heavily and run it into the neck-sizing die. There will be a visible lube ring showing how much of the case neck is being sized. Adjust the die until the lube ring is just shy of the case shoulder and all should go well.
This subject of reloading die versatility or lack thereof was driven home to me in 1968. I acquired my first .44 Magnum revolver but after firing a few full power factory loads I determined it would serve most of the time as a .44 Special. Not knowing better when I bought dies they were labeled “.44 Magnum” and would not seat and crimp bullets properly in .44 Special cases.
In the same year I acquired my first .45 ACP Model 1911 and Colt SAA .45 but being in college could not afford reloading dies and bullet molds for both rounds. So I bought dies and mold for .45 ACP and also used them for loading .45 Colts with dies properly adjusted of course. That system worked well for several years until I prospered enough to buy genuine .45 Colt reloading dies.
Today I have scores of die sets able to handle most any eventuality encountered in my reloading but an understanding of case dimensions and interchangeability helped me get through the lean years.
By Mike “Duke” Venturino
Photos By Yvonne Venturino
The Redding die set (top) is marked .44 Spl/Mag so it can’t be used to reload the
shorter .44 Russian. The RCBS die set (bottom) is marked .44 Russ/.44 Spl. However its
dies can also be adjusted to reload .44 Magnum.
In addition to loading the .308 (left cartridge), a .308 Winchester neck-sizing die can
also be used for neck sizing .30-40 Krag (middle) and .30-06 (right).