9mm specifications

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  • 9mm specifications

    The time has come to ask if anyone has the specifications;;;; case wall and base thickness for 9mm.

    I have heaps of 9mm, new and old, SOME a very few of 9mm+p, the question is, this +p does it have thicker walls, base?
    As next week I want to load 9mm in Major for my Czechmate I will start with ADI, AP100, begin at 6.5grns and work up to 7grns using 125 grn projectile, small rifle primer and an OAL of 1.12.

    I have had a great number of private messages and information from friends who advise, ""yes try this load, great, works for me" MY gun, I need to know.

    Hence if 9mm+p has thicker walls or thickness at the base perhaps this is a try. Loose less cases, or will the normal Winchester cases, Speers etc work?

    It is easier to ask then to re-invent the wheel, and it appears to me that there are some very smart people on this forum. In advance, thank you.

    All assistance will be greatly appreciated.

  • #2
    Bare in mind Susan, I don't load to those extremes of pressure.....

    I would go along and use +P cases, particularly if any part of the case is not fully supported by the chamber walls. If you had a fully supported chamber made to the smaller size SAAMI specs, then I would use standard 9mm cases.

    You may find US mil spec 9mm cases (WCC) cheap and once you remove the crimp, they are a stronger case than a commercial case.

    I hope this gives you some food for thought.




    • BulM5
      BulM5 commented
      Editing a comment
      Many +P cases are so marked only because they were loaded as + P rounds or intended to be. The case may or may not be identical to its standard variant. Easy way to sort them out is to weigh them. The external dimensions are standard and any extra metal inside a reinforced case it is not easy to see but the case will show up as being heavier.
      Your problem doesn't end there though. The thicker the case the smaller the available powder space which for any given powder charge means that pressure will be higher. The early experimenters who tried magnumising the .44Special and .38 special used the early thin headed cases designed for black powder. Of course revolvers support the case much better than Autos so they got away with it - most of the time.
      So my advice is don't worry whether its a standard or +P case. Just make sure all your cases are the same. The work out a load. If later you change to a different case, be circumspect and work you load up again.