I think we all have one of these friends:

A couple of years ago, I switched to two different storage methods for reloading. The first is a wall unit with removable bins. Lots of different sized bins available. You can get add on lids for the bins. All in all, a great choice.

Until I realized I had too much. From there I moved to MTM crates and ammo can crates. The simple crates are just sealable boxes of different sizes. Good handles on the side, and they can hold a fair bit. I started storing bullets and other gear of that sort in them. There is one crate that is nothing but misc magazines, for example.

The other crates hold 4 or 5 ammo cans each. 4 50 cal cans or 5 30 cal cans. They have some for their plastic ammo cans and some for regular GI metal cans. I use both.

A few months ago, I found some 8 mm Mauser boxer primer cases. I picked up 125 for a good price. This is good. I can now make freedom delivery systems for the K98. A week or so ago, my Redding 8×57 mm dies showed up. I resized 10 cases, measured them, they don’t need to be trimmed. All good.

I started my research knowing that 8×57 didn’t take the same bullets as 30-06 or 7.62×51 NATO. No problem. In my research, I found what, I thought, was a great piece of interest. This was from my reloading sources, so it was good information.

7×57 mm cartridges use the same bullets as .303 British. This is wonderful! I have lots of .312 bullets.

I can’t find them. They are nowhere to be found. I started tearing the reloading room apart. The crates labeled “bullets” are at the bottom of the stacks. And when I got to them, I found 1000s of bullets. None of them .312.

I became more methodical. I started opening every can to check what was in them. On about the 15th can I open, a 50 cal can, I find it has the neat trays in it. It was at that point I remembered that I had put a number of bullets in those trays, to make it easy to find.

Sure enough, I find my Hornady SST .312 150gr bullets. This is wonderful. I weigh and measure the bullets. 150gr, 0.312, all good. I pull open my sources, yep, 7×57 takes .310-.312. Everything is going well.

I open up my reloading book, pick my powder, IMR 4895, start writing down my planned loads. I’m just about to prime the cases when I look at the bullets and the cases. Those necks look bigger than the bullets. I take a bullet, put it in the neck of the case and it falls in. That neck is larger than the bullet by an unreasonable amount.

Back to the books, 7×57 is 0.310-0.312… Whiskey-Tango-Foxtrot? The references are 7.92 mm by 57 mm. So, 0.312 does seem a little small.

Back to the books, 7×57 is still 0.310-0.312

DOH. No wonder I was rounding off the corners.

I want 8×57, not 7×57.

The Mauser is available in many calibers. 7.92 mm is expressed as 8 mm in the references. They also make a 7.62 by 57 called the 7×57 mm. I was looking up the wrong data.

Be careful out there.

Here’s a higher resolution video by Curb.

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By awa

7 thoughts on “Tuesday Tunes”
  1. Regarding projectiles for your 7.92×57, you need to check if yours is the I or S version, the I uses .318 diameter bullets, while the S uses .323. The 7×57 uses .284 diameter bullets. The book Cartridges of the World explains the reasons for the different diameters for the 7.92×57, which we in the US typically call the 8mm Mauser.

    1. Thank you, John. I just double-checked the markings. This is a 1943 K98 manufactured by Mauser, Obendorf, marked “byf” “43” on the top of the receiver/barrel. My rifle has the proper proof markings in all locations, but the bolt has a different serial number from the rest of the rifle. The bolt has the same serial number in all three locations and proper proof markings.
      .
      I believe I have heard of the “I” and “S” versions of the rifle, but I have no idea how to go about making that identification. If you can point me to a source to make that identification, that would be greatly appreciated.
      .
      Meanwhile, I’ve been shooting military surplus 8 mm Mauser from it. The head stamps are 7.92 mm, and they measure out at 0.322

      1. Every 8×57 round is an “I” – that simply means “infantry”. Because it looked like a “J” to American and British troops it is also known as “J”.
        They switched to “S” before WW1 – in 1903. So every K98k, vz.24, LaCoruna and what else is “IS”. Even virtually all G98 are “S”. Most rifles that are NOT “S” are G88 rifles and turn of the century hunting rifles – and some very very very rare military G98.
        “S” means “stark” (strong) as in “a stronger diameter”.

        1. Thank you. If I remember correctly, you are from Europe and deal with firearms there. This makes sense. And it means that I can continue my search for a source of 0.320-.323 bullets.

          1. German gunsmith. As such we were indoctrinated about the superior of the 8x57IS.
            Just like the Kaugummisoldaten were taught about the superiority of the .30-06 Springfield 😛

            Some sources state that the “S” stands for “Spitzgeschoss” (Spitzer) but I only encountered that term in english sources and it would be unlikely given that the Germans did designate their projectiles separately. I think it comes from the fact that the “S”-Patrone introduced a Spitzer-bullet.

        2. I’m looking for a sling for my K98. Can you give a pointer to a good repo? I’m interested in something that looks period correct, I’m not set on paying for something from 1943.

  2. That reminds me of a moment of terror while loading .308 Winchester. I was picking bullets out the box of Hornady 165gr Interlock and setting them in the cases when one dropped completely in instead of an interference fit. After a moment of terror that I had screwed up my sizing die I compared it with another bullet and realized Hornady had accidentally dropped a 7mm bullet in my box of 7.62mm.

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