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For the 45GAP shooters

Discussion in 'Reloading' started by dudel, Apr 16, 2010.

  1. dudel


    Dec 10, 2008
    Texas Hill Country

    "The internal case wall profile is significantly different from .45 Auto cases to permit seating .45-caliber bullets without bulging. The most obvious difference is that the .45 GAP uses a Small Pistol primer to put distance between the primer and breech/action elements present in 9mm-frame pistols. It is unsafe to cut off .45 Auto cases to make .45 GAP cases. The most significant issue is the difference in primer size. A Large Pistol primer that fits the .45 Auto case will over-ignite safe powder charges developed in proper GAP cases with small primers, and high pressure will result. The .45 GAP case has a much different internal taper, so cutoff .45 Auto cases will bulge when bullets are seated to recommended lengths."

    Be safe out there. Since it's not run of the mill brass, I hear many talking about cutting down 45ACP cases. Doesn't look like a good idea. Not to mention that 45ACP cases are not really high pressure ones.
  2. jeffreybehr

    jeffreybehr Silver Member

    Mar 14, 2009
    Phoenix, AZ USA
    I don't hear or heard of ANYONE shortening 45ACP cases for use in a 45GAP...but I don't get around much. :upeyes:

  3. PsychoKnight


    Sep 30, 2006
    SoCal - SGV
    This is an urban legend. People talk, but they don't do it.

    I did it. With both LP and SP .45acp cases (yes, there are many .45acp factory ammo brass out there which is outfitted with SP sized primer receives, and .45 reloaders complain everytime these are picked up from the range and mixed up with their standard brass).
    I should say I tried to do it. It do'hn work, at all - won't chamber in my chamber gauges so I don't bother trying to fire them in the gun. ACP case walls are too thick around the bullet grip area.

    No need to ever discuss or warn about this - reloaders won't get past first base nor proceed to a possible kaboom or other mishap. Let'em try on their own because those who don't believe will need to convince themselves - like me.
  4. HarveyatPC


    Mar 25, 2005
    Panama City, FL
    Try WinClean 45 brass. It works well (SP primers).
    Last edited: Apr 29, 2010