Monday, February 15, 2010

Day 3: 10mm Ammunition

At the range this past weekend, we decided to run a brief test of a few of our favorite factory loads for the 10mm auto cartridge. Although reloading ammunition is a much more cost-effective method of practice, most people would agree that factory loads are necessary for self-defense ammunition for a carry or nightstand piece.

Ammunition Tested (pictured above):
  1. Double Tap 180 grain FMJ Match [1250 fps / 625 ft-lbs]
  2. Double Tap 200 grain FMJ Full Power [1275 fps / 722 ft-lbs]
  3. Double Tap 200 grain WFNGC Hardcast [1300 fps / 750 ft-lbs]
  4. Winchester 175 grain Super-X Silvertip JHP [1290 fps / 649 ft-lbs]
  5. Double Tap 200 grain Controlled Expansion JHP [1250 fps / 694 ft-lbs]
  6. Double Tap 230 grain Equalizer [1040 fps / 553 ft-lbs]
  7. Buffalo Bore 180 grain Heavy JHP [1350 fps / 782 ft-lbs]
Full Metal Jacket / Solid Rounds:

Double Tap Full Power FMJs are great for any application where you need intense firepower in a solid projectile. If you feel like you're bound by the Geneva Conventions (or more correctly, the Hague Convention) and NATO guidelines, these would be the rounds for you. They're also great if you're looking for rounds with penetration rather than for normal defensive carry. The FMJ Match ammo from Double Tap comes with a $1 price break per box. At that rate, why not get the heavier full power loads?

The WFNGC Hardcast loads from Double Tap are what I use for carry in the woods. The flat tip is designed for cutting bone rather than deflecting off, and is advertised by the manufacturer specifically for hunting to create "create a large deep wound channel". These are fun rounds, and I highly recommend them. Many people warn about firing lead rounds through Glock factory polygonal rifled barrels due to excessive fouling and subsequent pressure issues, so if you plan to shoot a large number of lead rounds you might want to invest in an aftermarket barrel. As for me, I just make sure I keep my barrel clean.

Like I said, we reload our ammo for practice bullets, which has the potential to save a lot of money. There's really no place to find economical 10mm ammunition for practice nowadays, and most manufacturers sell watered down crap that's basically .40 S&W. We avoid those manufacturers like the plague, and stick the with the good guys like Double Tap when buying factory ammo.

Jacketed Hollow Points:

And now for the fun part, field tests of JHP expansion!

We recovered fragmented jacketed hollow point bullets from a 2500 page hardcover catalog at 10 yards. This test was certainly less than scientific, but can provide useful field experience in the absence of better ballistic media. I will review the rounds in the following picture from left to right.

The first bullet in the series is an expanded Double Tap JHP, which I rely on for my carry pistol. In this and in previous tests, the brass jacket completely separated from the lead core, but did not otherwise fragment. I find this round to be the ideal combination of power and expansion, and is one of the few 10mm hollow points to come in a heavy 200 grain configuration.

The Buffalo Bore JHP penetrated farther than Double Tap, but had the harshest recoil characteristics of all the rounds tested and completely fragmented in the catalog. The published ballistic data on this round resulted from tests with a Colt Delta Elite, which has a barrel .5" longer than the Glock 20, that Double Tap uses for their tests. This may exaggerate the reported muzzle velocity and force, but I think it is fair to say that Buffalo Bore matches or slightly exceeds the Double Tap JHPs in terms of energy. The recoil increase is noticeable.

I do want to mention that this was the first time I've fired this particular round, and my gun happened to lock up after the very first bullet, which I shot from an otherwise empty magazine. The brass ejected (farther than usual), I dry-fired to de-cock the hammer, and after loading a fresh magazine was unable to cock the firearm. This very well may have been a fluke, or it may have been due to the excessive recoil jarring the recoil spring or kicking loose debris somewhere in the slide. I keep my guns meticulously clean - and it is a Glock - but it was snowing, cold, and could have been anything. I will also mention that my G20 has an aftermarket 22 lb. recoil spring and steel guide rod, so it is tuned to handle hot rounds. Needless to say I would be reluctant to use Buffalo Bore as primary self-defense ammunition after this experience, but I'll need a lot more trigger time with this round before I can come to a good conclusion. Also, at over $1 per round, they are significantly more expensive than even Double Tap.

There is really nothing like the Double Tap Equalizers. This round is made up of a 135 grain JHP on top of a 95 grain lead ball, so it is essentially two distinct bullets in one case. These are a blast to shoot, and they're surprisingly accurate. We were able to recover both the ball and the hollow point from the target, right next to each other. I would personally never use such a nontraditional round for anything but range fun, but you never know when double the firepower could be useful during a zombie apocalypse!

Winchester Silvertips are Mini4me's current choice for 10mm self-defense loads. In this experiment, the hollow point failed to expand within the target, and penetrated deep into the catalog without mushrooming. After recovering the bullet, we noticed a chunk of paper in the center of the lead, clogging the opening and thereby preventing efficient expansion. The jacket remained intact with the bullet core, which did not happen with the other rounds. I want to again emphasize that this does not directly extrapolate to fleshy targets or layers of clothing, so just take it for what it's worth.

The problem with this result is that it has implications to self-defense. There are alleged reports of hollow points becoming clogged with heavy fabrics in human targets, preventing adequate expansion and effectively becoming a full metal jacket round. The end result is decreased energy transfer, weaker knock-down power, and more limited tissue damage. If my life were on the line, I'd want to be able to depend on my bullet's expansion.

The round of the day award would have to go to the Double Tap Equalizer. You just can't beat two bullets in one cartridge!

I hope you all had as much fun reading about these rounds as we did shooting them… Of course that's impossible, but if you have any personal experience with these or other 10mm cartridges, let us know!


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  2. Nice information regarding 10mm ammunition.
    Thanks for sharing such a useful information.
    Please keep it up.
    10mm ammunition