Pat's Notes from the Field: Freedom's 10mm Auto

The 10mm Auto is a neat and unique cartridge.  It can trace its origins to the minds of several notable gun-guys over the years, but much credit is given to Colonel Jeff Cooper (you better know who that is, if not look him up!). Col. Cooper felt that an auto pistol cartridge with a flatter trajectory than the 45acp and more horsepower than the 9x19 would be a worthwhile addition to the law enforcement arsenal.  Without going into the full history of this fine flat shooter, the 10mm was created in concert with the ammo crafter Norma of Sweden and makers of the Infamous Bren 10 pistol, Dornaus and Dixon. Based on a cut down 30 Remington case, the 10mm Auto in its final ballistic specification exceeded expectations.  Not only was it flatter shooting than the little 9mm, it pushed well past the 45acp in muzzle energy, especially at longer ranges!


The Freedom Munitions loading that I tested here is just a bit short of some of the first offerings of this cartridge. Early lots of factory Norma 10mm ammo drove 170 grain bullets nearly 1300 feet per second and 200 grain bombers at 1200!  Those numbers encroach on 41 Magnum territory!!!


While an individual can load to those levels, and some boutique makers do, some guns and many a shooter found themselves rattled a little loose by the Norma (magnum) 10mm Auto experience.  Over the years the powerful 10mm was "dumbed down" to where the powder charge could be housed in a smaller case...and that got us the 40 S&W.


I am happy to report that Freedom Munitions didn't neuter the 10mm Auto.  While it runs a little shy of pushing a 180 grain bullet to 1200, it does have the 180 grain Hornady XTP moving along, averaging 1140 out of my Glock G20.


Accuracy is what I have come to expect out of this particular Gaston Gun. Please note that the 5 shot groups shown are the best 5 of 6 shots fired.  I am human and was not having the best day at the range.  I think it was Massad Ayoob that started this practice years ago, explaining that "one is testing the firearm, not the tester" or some such. So the using of the "best 5 of 6" is more indicative of what the gun and load are capable of and I agree. Below are six groups fired from a rest at 25 yards. Average for the 30 total shots 2.03".


Freedom's 180 grain XTP 10mm load shows itself to be a worthy destructive device on errant cans of shaving cream.


I am a fan of the 10mm and have several guns so chambered, but am always looking for another, why?  Because the Freedom Munitions 10mm load is just about everything I want in a 10 sans a couple feet per second. Accuracy, Power and Speed...hmmm where have a heard that before? D.V.C. anyone?


  1. Phil B. 25 December, 2016 at 19:20 Reply

    I love the article, but I must note, that in order to determine the best 5 out of 6 shots fired, one must fire a 6 shot group. Not trying to negate or argue. Like I said I loved the article. I love 10mm myself and found this to be quite informative.

    • Patrick E Kelley 27 December, 2016 at 19:45 Reply

      You are a sharp guy! I dig that you really read and looked over the article…thank you!
      I did break a 6th shot on most every group, but it is hard to see in the photo where “taped them up”

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