Help, 8mm ammo is damn confusing...

[Rockrivr1]

Some years ago I bought a nice Mauser with several bandoleers of 8mm ammo on 5 round stripper clips. It's a great old rifle that I put into the back of the safe where it sat for a few years until just recently. After a fun range trip I'm down to the last bandoleer of ammo so I went looking to pick more up and am now a little confused.

I wanted to make sure I'm getting the right ammo as there seems to be a few different 8mm. There is 7.92x57, and 8x57, and 8mm Mauser, which I'm thinking might all be the same. But then what is 8x57JS and 8x57JRS? Then I read something about some of the old Mausers being in an "old" 8mm boresize. What the hell is that???

So need a little help on what I'm actually looking for.

Thanks

 

[dhuze]

"Old 8mm" There is more than one way to measure 8mm?

Go with 8mm Mauser. That's what I do.

Just looked at my stash and it's 7.9. same difference though.

 

[tk421991]

Wikipedia covers this pretty good.

The official metric designation is 7.92x57. The normal American word is 8mm Mauser or 7.92 Mauser. Some surplus ammo like Yugo will say "7.92" and then something in Cyrillic, I think the transliteration is "metaka" - cartridge. It can also be shortened to just 7.9/7.9mm. JS and IS is what you want if you aren't shooting a M1888 Commission rifle. J/I = Infantry and S = spitzgeschoss, spizter bullet. In English, J is used to translate the German letter I - don't know why.

"R" means rimmed, like 7.62x54r. 7.92x57JRS or IRS is made for breechloading double or drilling rifles. You need a rimmed piece of brass to hold the cartridge in place in the chamber, like how you can have a .30-40 Krag Sharps rifle and how shotgun shells work in a O/U or SxS.

The current bullet diameter for 7.92x57 is .323". This size was adopted around the turn of the 20th Century. The old bullet diameter is .318" and is/should only be used for M1888 Commission rifles.

 

[rivet_42]

In English, J is used to translate the German letter I - don't know why.

In the German Fraktur typeface that was common prior to WWII, the capital letter "I" has an extra hooky-jigger on it so it looks to English speakers like a "J".