Let's Talk Reloading the 8mm (7.92) Mauser...

Discussion in 'Ammunition & Reloading' started by Joshua M. Smith, Aug 18, 2011.

  1. Joshua M. Smith

    Joshua M. Smith New Member

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    Hello,

    I just ordered 20 pieces of brass, 50 200 grain 0.318" soft point bullets, and dies for my new, 119-year-old Gewehr 88.

    From what I gather on numerous boards, since mine is "S" marked, it can theoretically take 0.323" bullets, but because it slugs to 0.316" or so, I'm not going to risk it.

    Additionally, I've read that the locking lugs and overall steel aren't as strong as the later Mauser, so it needs to be loaded back, 2000fps to 2500fps max.

    In looking at the data on Hodgdon's website, it looks like two of my favorite powders, Varget and H4895, are used on both the 8mm Mauser and the 7.62x54R, so one of the two make logistic sense for me to use.

    Looks like my shell holder for my .45acp will work just fine on the Mauser round, as well.

    So, recipes folks? Or do you just use the starting loads?

    I can't wait to take a few shots from this ol' warhorse!

    Any advice is appreciated.

    Thanks!

    Josh
     
  2. Bigdog57

    Bigdog57 New Member

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    Steve Ricciardelli's loading pages are often a good place to start.

    318_1

    His heaviest load goes to 196 grain, but this should be close enough - back off ten percent beginning, and look for the usual pressure signs.
    What I do, rather than immediately trust an 'internet load', use your Google-Fu and check various other loading data sites for the same caliber loads.
    Cross-check to make sure you aren't using a 'hot' load!
     

  3. Joshua M. Smith

    Joshua M. Smith New Member

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    Thanks Gents.

    Bigdog, I'm definitely looking there!

    Now, the data I've found on the 8x57j round suggests that the maximum pressure should be 37,500 CUP. According to Hodgdon, the starting loads for the 8x57JS (Mauser) round are right below that, but they also use 0.323" bullets as opposed to the 0.318" bullet of the 8x57j.

    Should I start at 10% below their stated minimum (I've decided to use Varget) and work my way up, using the minimum as maximum? Or would this be a bad idea?

    Thanks,

    Josh
     
  4. Bigdog57

    Bigdog57 New Member

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    The basic load data should be okay - the thing we need to watch is the larger bullet in the smaller bore would increase pressures. The difference in bullet diameter should not affect the data if you are using the smaller bullet. The difference is negligible - if the bullet WEIGHT is different, that is a different matter!
    This is like loading the 7.62X54R with a .308 vs. a.312 bullet - same data. We just keep the bullet diameter matched to the bore size.
    If your bore really IS the later "S" bore, the worst you will see is a wider group when shot.
     
  5. jpattersonnh

    jpattersonnh Active Member

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    Begin w/ starting loads. I use IMR4320 for 8x57IS(JS). Very stable powder, not affected by temperature.
    If your load is to light, That could give you pressure spikes. Cartridges of the world has both .318 and .323 together in the U.S. section, but seperate in the european section.
     
  6. Joshua M. Smith

    Joshua M. Smith New Member

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    Hello,

    I decided to go with a powder I know -- and Trail Boss was out, anyway.

    Thus far I've fired two rounds. Both were 0.318" 200grn JSP over 40.5grns of Varget. That's a starting load for the 7,9x57js, but right in the middle of the pressure curve for the j. Also got a pamphlet with about all the loads out there for the j and js.

    Now,the first round was fired remotely from behind ballistic glass as suggested by JayPee. I opened the breech, inspected the cartridge, bolt, etc for damage. Everything looked perfect, so I fired the next one manually into a dead tree about 25 or 30 yards distant.

    It went right where i wanted, but a couple inches high.

    I'm pretty sure the guy who had this before me had been running surplus (eek) through it as evidenced by the bore's condition. If that's the case, this old warhorse is getting a break.

    Range report to follow after I test the cycling!

    Regards,

    Josh