By Art Merrill | Contributing Editor
There are still plenty of the old .318” bulleted 8x57J Mauser rifles around.
Maybe you’ve already experienced the puzzlement that dissolves into frustration when a cartridge won’t chamber and you suddenly discover you’ve brought the wrong ammo to your plinking spot—the big match—your African safari. Aggravating, sure, but on the positive side, it can be much worse when the ammo fits but it isn’t the correct ammo.
One example is the 8×57 Mauser, aka 8x57JS, 7.92x57mm and 8mm Mauser. This cartridge started life in 1888 as the 7.9x57mmJ (“J” actually being the German letter “I” for “Infantry”) with a bullet .318” in diameter and barrel bore lands of .311”. Neither of the Mr. Mausers designed the cartridge; it is based on a preexisting Mannlicher design. And the rifle for it, the Gewehr 88 or Model 1888, wasn’t a Mauser design either; the German Infantry Commission cobbled its features together and hired Peter and Paul Mauser to make it.
Handloading the .323” bulleted 8x57JS (center) into nickel plated cases helps ID it to prevent confusion with 8x57J (left) and .30-06 (right) cartridges.
Quick change
As with anything decided by committee, the Model 1888 had lots of room for improvement, which Paul Mauser recommended and Germany incorporated in the famous Model 1898 only a decade later.
Common markers in various color combinations will pair your ammo to specific guns, and they leave no buildup on cases.
Improvement to the ammunition included lightening its 226-grain bullet to 154 grains, sharpening its round nose to a spitzer point and increasing its diameter to .323”. The changes raised muzzle velocity nearly 800 fps to 2880 fps—slightly faster than the US Government .30-06. Germany converted its arsenal of Model 1888s to accommodate the changes, and by 1905 all 8mm Mauser rifles came from the factory barreled for .323” bullets. The new designation for the cartridge became 8x57JS, the “S” referring to the spitzer bullet. This is the cartridge we get today when we ask the gun store clerk for “a box of 8mm Mauser.”
However, there are still plenty of 8mm sporting rifles out there that require the .318” bullet and, as you can imagine, firing the .323” bullet through a .311” bore is not a good thing. Unfortunately, the larger bulleted cartridge fits readily into chambers intended for the smaller, so it is up to the shooter to ID and use the correct ammunition.
Documented kabooms
But that’s not all. Both the .318” 8x57J and the .323” 8x57JS also might fit in some oversize .30-06 chambers. If swaging a .323” bullet down to .311 via a 50,000psi+ explosion a few inches from your face is a bad idea, then attempting to swage it down to .308” in the same manner is even more so.
Attempting to chamber an 8x57JS cartridge in a .30-06 rifle usually results in finding it impossible to close the bolt. This is as it should be but, as unfortunate soldiers likely discovered as early as the Great War and which became documented fact in the 1920s, it is not impossible 100 percent of the time.
Major General Julian Hatcher (1888-1963), former US Army Chief of Ordnance and well respected for his technical knowledge of and experience with the .30-06 cartridge and small arms, named and dated specific incidents of the inadvertent firing of the 8x57JS in .30-06 rifles. In November 1921 Hatcher examined a Springfield rifle that suffered a catastrophic failure (a “kaboom”) at Sandy Hook Proving Grounds in which Pfc. Thomas P. Appleby lost an eye. Hatcher found the remains of a cartridge case in the rifle chamber. “When this was removed,” he said, “it turned out to be a German 7.92mm military cartridge.”
Hatcher reported similar incidents at Army posts October 27, 1925; August 19, 1926; and July 13, 1927. Routine reporting of these mishaps ceased in 1929, Hatcher having concluded that minimum size tolerance 8x57JS cartridges can fit in maximum size tolerance .30-06 chambers of Springfield rifles.
Brass ID
After firing there is still enough marking left to ID your brass from others’ on the firing line.
I have two rifles chambered in 8x57J, a couple more with 8x57JS bores, and plenty of .30-06s, including a number of Springfields. Mr. Safety (that’s me) wants to take every reasonable precaution to ensure I don’t inadvertently try to shoot the 8x57JS in my 8x57J or .30-06 rifles, so as an immediate visual aid to ID my .323” bullet diameter 8x57JS cartridges, I load them in nickel plated brass cases. There is no possibility of mistaking the shiny nickel cases for ordinary brass color.
Which allows us to segue into the broader question, “How can I color my brass to ID it for other specific purposes, in such a way as to not add material to the case that would interfere with proper chamber fit?
Highpower Rifle competitors who handload for semi-automatic rifles put a lot of work into prepping match grade brass and we like to get it back when the match director makes his call to police the firing line; the common practice is to ID our own brass by marking cases with a common permanent marker. I mark mine, for example, with a black and/or red stripe across the headstamp and primer. Much of the mark comes off upon firing and the rest comes off during cleaning in the case tumbler and so I have to mark fresh handloads again. But it works!
Some other marking materials, such as nail polish or other lacquer, may leave residue in the chamber or action after firing or be thick enough to interfere with precise chambering or headspace. Applying it into the case extractor groove could possibly interfere with reliable extraction. Whatever marking material you try, also be sure it doesn’t chemically attack the brass.
Certain chemical mixture baths can color brass green, blue, red, black or brown. However, they are not common household chemicals, many are sold only in large bulk and they can produce toxic fumes. Several recipes include ammonia, which has an appetite for copper (the reason why many bore cleaners that dissolve copper bullet jackets smell like ammonia), and brass is an alloy of about 70 percent copper and 30 percent zinc. You can see the potential for ammonia weakening brass cases. For all these reasons Mr. Safety will eschew the brass case chemical bath path and continue with simple markers and nickel plated cases.
Gun and cartridge: ‘Hollywood marriages’
The Sporting Arms and Ammunition Manufacturing Institute (SAAMI), which sets agreed-upon industry standards for firearm chamber dimensions and ammunition dimensions and pressures, has a list of guns and ammo combinations not meant for each other. Some bad combinations—such as firing a .308 Win cartridge in a .270 Win chamber—have occurred often enough to become classic examples of Hollywood marriages. The SAAMI list, beyond an interesting who’s-who of “I didn’t know that” combinations, serves to remind us that inattention and complacency attracts Murphy as readily as does bad advice – and that there is only one safe and proper cartridge/chamber combination. For a free PDF version of the SAAMI list go to
