Privacy guaranteed - Your email is not shared with anyone.

Welcome to Glock Forum at

Why should YOU join our forums?

  • Connect with other Glock Enthusiasts
  • Read up on the latest product reviews
  • Make new friends to go shooting with!
  • Becoming a member is FREE and EASY

Glock Talk is the #1 site to discuss the world’s most popular pistol, chat about firearms, accessories and more.

40 cal bullets in 10mm shells

Discussion in '10mm Reloading Forum' started by lunker, Oct 14, 2010.

  1. I have been using 165grain Montana Gold FMJ bullets with various brass. I have been loading to the accepted 1.26 OAL. Visually though, the bullet seems as though it is set too far back in the case. I will be buying the 180 grain bullets next time I order. Has anyone else noticed this phenomenon? I will post a picture or two when I get home tonight.
  2. Kegs

    Kegs Ol 8 fingers ;)

    Oct 26, 2009
    Cold side of conus
    -How long are your cases?

  3. I will measure a few when I get home, but they are standard Starline, Winchester, Georgia Arms brass. I discard brass that starts to exhibit signs of wear, so I don't think the length is out of spec.
  4. Kegs

    Kegs Ol 8 fingers ;)

    Oct 26, 2009
    Cold side of conus
    Well if your brass is .982-.992" and your COAL is 1.26", it should look like pretty much any other 10mm cartridge out there.

    Have you calibrated your caliper lately? :supergrin:
  5. I would think so too. I was wondering if the MG bullets I was using were more "configured" for 40S&W. Since the 40 has a different OAL, I was thinking that perhaps the design of this bullet was more designed for how much it would protrude from a 40S&W case than a 10mm case.
  6. Kegs

    Kegs Ol 8 fingers ;)

    Oct 26, 2009
    Cold side of conus
    That would be the first time I'd ever heard about it. I never had any problem with the appearance of the 155gr. xtps vs. 200 gr. ones - just more of the 200 in the case - but I haven't really used any other bullets other than the XTPs so far - though I have seen the M.G.s loaded in the double tap rounds I purchased a year ago - they didn't really look that much different - until you shot them of course. :supergrin:
  7. The picture below has a 165 grain Speer Lawmen round on the left and a 165 grain Montana Gold bullet in a 10mm case. You can see that they differ in how far they are set back in the case.

    Last edited: Oct 14, 2010
  8. Kegs

    Kegs Ol 8 fingers ;)

    Oct 26, 2009
    Cold side of conus

    The .40 looks short and weak. :rofl:
  9. anomad


    Jan 9, 2003
    I load Speer gold dot 180's in 40 and 10mm cases. I seat them out a tiny bit farther in .40, just to be on the safe side.

    As long as there are no adverse pressure signs and your magazines feed reliably I'd say you're good to go.
  10. _The_Shadow

    _The_Shadow Ret. Fireman

    Jul 23, 2007
    Southeast, LoUiSiAna
    Bullets for the 10mm do seat deeper inside the casing of the 10mm as compared to the 40 Short & Weak. (exposed bullet that is) That being said that is how they get more powder space for the short 40S&W.

    Compare your to factory 10mm and you will see you are at the correct cartridge lenght 1.250" to 1.260". People have loaded longer but that is their personal preference which fits their particular weapon. If they swap to another weapon it may not work the same...
  11. Thanks Shadow. That is the missing piece. I really need to look at some factory 10mm ammo. At least I don't feel like. I might be screwing up my loads any more.
  12. texas 48

    texas 48 Gold Member

    May 19, 2007
    San Antonio, TEXAS
    I have loaded 3000 MG in 10mm from 1.250 to 1.260 no issues. Here is some data on different 10mm bullets.
    165 MG JHP .58 inches. 165 REM Golden Saber .57 Inches. 155 Hornady XTP .55 Inches. 150 Nosler JHP .53 Inches. 135 Nosler JHP .49nches. .40 is 10MM and vice versa
  13. herdingcats

    herdingcats still new

    Aug 20, 2010
    Seattle, Washington
    The pic you posted looks fine to me. I've loaded TONS of MG 155gr and 180gr JHP into both 40S&W and 10mm. I've kept my OAL to spec and have not had any issues. MG makes great stuff in my book.

    Unfortunately, I have not loaded the specific bullet you're referring to... the 165grain Montana Gold FMJ. So I have no info on that one.