INTERCHANGEABLE CARTRIDGES?

Just about everybody knows that the .38 Special and .357 magnum cartridges are partially interchangeable – that is, .38 cartridges may be fired in a .357 mag chamber. The opposite, however, is not true, as a .357 mag will NOT fit or fire in a .38 Special, because the cartridge case is longer, and this is a good thing, because .38’s are not made to take the pressures of a .357. The same relationship exists between the .44 Special and the .44 magnum – “Specials” will fire in Magnum revolvers, but Magnums are too long for .44 Special chambers. Owners of either of the magnums can use the lower powered, lower priced “Special” ammo for target or self-defense shooting – without the need to hand load – and also benefit from the much reduced recoil.

.44 Special vs .44 magnum - a .44 Special round will fire in a .44 magnum  safely, but a .44 magnum round will not chamber in a .44 Special revolver.

.44 Special vs .44 magnum – a .44 Special round will fire in a .44 magnum safely, but a .44 magnum round will not chamber in a .44 Special revolver.

The .38 Special cartridge will chamber and fire in a .357 magnum, but not the other way around.

The .38 Special cartridge will chamber and fire in a .357 magnum, but not the other way around.

The .44’s and .38/.357’s are RIMMED cartridges, which means they “headspace” by the rim keeping the cartridge in it’s proper position in the cylinder, not letting a “Special” of either caliber slide deeper into a Magnum chamber. This is a benefit of rimmed handgun cartridges that is sometimes overlooked.

Working with the .460 Rowland cartridge has resulted in my seeing several comments on the inna net about shooting .45 ACP cartridges in .460 Rowland barreled pistols. The Rowland is actually a .45 caliber, shoots the same bullets as the .45 ACP, for the most part, and can be reloaded using the same dies. The difference is that the cartridge case is longer. The .45 ACP round WILL fit in a Rowland chamber, but since semi-auto cartridges “headspace” on the mouth of the cartridge case – having no rim – the cartridge will fit much deeper into the chamber than it was intended. (the .460, however, WILL NOT chamber in a .45 ACP). Some will say the extractor will hold it in place and it can be fired, but this is not the job the extractor was intended for, and accuracy would certainly be less than stellar if the round did fire. The action also might or might not cycle. All things considered, not a good idea to try this.

The .40/10mm and .45 ACP/.460 Rowland share a situation where the same bullet diameter is used, but the cartridge case length is different. This is partially to avoid the larger rounds being chambered in pistols intended for the less powerful cartridge. Being rimless, a .40 will not chamber properly in a 10mm, nor will a .45 ACP in a .460.

The .40/10mm and .45 ACP/.460 Rowland share a situation where the same bullet diameter is used, but the cartridge case length is different. This is partially to avoid the larger rounds being chambered in pistols intended for the less powerful cartridge. Being rimless, a .40 will not chamber properly in a 10mm, nor will a .45 ACP in a .460.

Pretty much the same relationship exists between a .40 and the 10mm. Both fire a .40 bullet, but case lengths are different, and since they are rimless semi-auto cartridges, the same problems occur as with the .45 ACP/.460 Rowland.

If you have a 10mm or .460, and for some reason want to shoot a less powerful cartridge in it, it is not that difficult to change the barrels to the “lesser” round in either a 1911 platform, or a Glock in the case of the 10mm (mine, anyway, but if you are fortunate enough to have a 10mm 1911, the same thing applies – if you can find a .40 1911 barrel). With the Rowland in a 1911, the same magazines will work, also. Having the “extra” barrel makes for a more versatile handgun, and if you converted your .45 ACP to .460, you should have that barrel already.

For those who don’t want to change barrels to shoot a less powerful round for whatever reason, reloading is the other option. Either a 10mm or a .460 CAN be loaded down to .40 or .45 ACP specs. The only problem that might be encountered could be that the action will not cycle properly, due to the heavier recoil spring used with the more powerful cartridge if you load down too much. When changing barrels, of course, simply also change the spring.

Personally, I find it better for me to just have two pistols than to be changing barrels or complicating my reloading. To be honest, I feel almost the same way about my Contenders, and changing barrels on them is much easier.

Of course, maybe it is just an excuse to have more handguns?

About MikeH

Texas hunter and fisherman for 50 years, published outdoor writer since 1979, licensed charter boat operator from 1982 to 2013. Past Member, Board of Directors, National Association of Charterboat Operators, current member Environmental Advisory Committee to the DOE and the Strategic Petroleum Reserve. Married to Dorothy since 2000, one son, Michael who is recently married and living in Nederland, Texas. My wife and I live in Oyster Creek, Texas, near Freeport, and have a hunting property outside of Brazoria, Texas.
This entry was posted in Rifles and Other Things That Go Bang!. Bookmark the permalink.