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Does Downsizing Make Sense

Does Downsizing Make Sense

Just what are you giving up when dropping from 9mm to .380 acp?

By Richard King

The Hand Guns

Selecting a caliber for the perfect defensive handgun is a topic that some folks could debate for hours. Perhaps you've even engaged in some banter pointing out how calibers the size of lug nuts are superior to rounds resembling your grandma's earrings.

When you go into your favorite gun store to purchase a small pistol for concealed carry, caliber is probably one of the first things you consider. Picking up a pistol chambered in .44 Magnum might make you want to eat a pound of bacon and yell “'Murica!” at the top of your lungs, but if you can't hit a stop sign at 15 yards with it, how useful is it?

Technology has changed drastically over the past 10 years, and so has bullet design. Simply claiming smaller calibers are inferior just won't cut it anymore. In this assignment, we'll examine two of the more popular small calibers, 9mm Luger and .380 ACP. Both are popular choices for citizens exercising their Second Amendment rights, as well a standby option in backup guns for law enforcement. These calibers are also a good starter caliber for new shooters, since guns chambered in the smaller round often have less felt recoil.

We conducted our ammo tests using two popular CCW handguns, the Glock 42 and Glock 43. Both are small, slim polymerframed pistols with a single-stack magazine and proven reliability.

We tested four different brands of some of the best-selling ammunition based on sales from Brownells.

BROWNING BXP X-POINT

9mm 105-000-882: 147-grain hollow point with X-Point technology designed to shield the hollow point through intermediate barriers. This projectile has 326 ft-lb of energy, traveling at 1,000 fps.

  • $17.99 for 20 rounds
  • $0.90 per round

.380 ACP 105-000-881: 95-grain hollow point with the same X-Point technology designed to shield the hollow point through intermediate barriers. This projectile has 211 ft-lb of energy, traveling 1,000 fps.

  • $17.99 for 20 rounds
  • $0.90 per round

G2 RESEARCH R.I.P. AMMO

9mm 105-000-420: 92-grain hollow point machined from solid copper with detaching trocars that create nine separate wound channels. This projectile has 327 ft-lb of energy traveling at 1,265 fps.

  • $37.50 for 20 rounds
  • $1.88 per round

.380 ACP 105-000-421: 62-grain hollow point machined from solid copper with detaching trocars that create seven separate wound channels. This projectile has 198 ft-lb of energy traveling at 1,250 fps.

  • $36.40 for 20 rounds
  • $1.82 per round

RUGER ARX

9mm 780-002-772: 80-grain injection molded ARX projectile from a specially blended copper/polymer matrix designed to be tough enough to penetrate soft targets and tissue, but when it encounters tougher barriers it breaks apart to reduce the risk of collateral damage caused by over-penetration. The ARX relies on fluid dynamics to slow the projectile down, rather than expansion. This projectile has 385 ft-lb of energy traveling at 1,445 fps.

  • $19.99 for 25 rounds
  • $0.80 per round

.380 ACP 780-002-770: 56-grain injection molded ARX projectile with the same design features as the 9mm version. This projectile has 215 ft-lb of energy traveling at 1,315 fps.

  • $18.99 for 25 rounds
  • $0.76 per round

SIG SAUER ELITE PERFORMANCE

9mm 105-053-353: 147-grain SIG V-Crown Jacketed Hollow Point bullets with a stacked design, featuring a smaller additional hollow point cavity behind the main cavity, providing controlled, uniform expansion. This projectile has 317 ft-lb of energy traveling at 924 fps.

  • $13.99 for 20 rounds
  • $0.70 per round

.380 ACP 105-000-329: 90-grain SIG V-Crown Jacketed Hollow Point bullets with a stacked design featuring a smaller additional hollow point cavity behind the main cavity, providing controlled, uniform expansion. This projectile has 192 ft-lb of energy traveling at 980 fps.

  • $14.99 for 20 rounds
  • $0.75 per round

TESTING

The FBI ballistic test protocol for heavy clothing was obtained from Buford Boone, former head of the FBI's Ballistic Research Facility. Boone told us to cover a 10-percent gelatin block with four layers of clothing: one layer of cotton T-shirt material, approximately 5.25 ounces per yard (48 threads per inch); one layer of cotton shirt material, approximately 3.5 ounces per yard (80 threads per inch); one layer of Malden Mills Polartec 200 fleece; and one layer of cotton denim approximately 14.4 ounces per yard (50 threads per inch). This simulates typical clothing worn in cold weather. The block is shot 10 feet from the muzzle and the projectile penetration is measured. Acceptable penetration for the test is no less than 12 inches and no more than 18 inches.

Before testing began, each round was fired into a bare ballistic gelatin block to get a baseline for expansion and penetration. After measurements were gathered, the heavy clothing layers were constructed and attached to the front of the gelatin block, and the test was conducted again. The chart to the right shows the findings of each round, at one round per test.

Round Type Bare Gelatin Heavy Clothing
Browning BXP X Point 147gr 9mm 18.5 inches 20.5 inches
Browning BXP X Point 95gr .380 ACP 9.5 inches 25.5 inches
G2 Research RIP 92gr 9mm 14.25 inches 11.5 inches
G2 Research RIP 62gr .380 ACP 9.5 inches 9.25 inches
Ruger ARX 80gr 9mm 14.75 inches 17 inches
Ruger ARX 56gr .380 ACP 13.25 inches 17.5 inches
SIG Elite 147gr 9mm 18 inches 17.5 inches
SIG Elite 90gr .380 ACP 8.75 inches 22.25 inches

As you can see from the results, maintaining the 12- to 18-inch penetration the FBI protocol requires is tough when heavy clothing is introduced. With hollow point projectiles such as the Browning and SIG, heavy clothing tends to clog the front of the bullet and prevent it from expanding. Because the bullet fails to expand it maintains velocity and acts like an ice pick as it travels through the target.

Projectiles like the Ruger ARX that are of a different design don't have expansion cavities to clog up. Rather than traditional expansion, the Ruger ARX relies on fluid dynamics to slow the bullet down. When harder barriers are encountered, the projectile is designed to break up to prevent over-penetration. In this test, the 9mm ARX projectile did just that. Instead of over-penetrating, the tip of the projectile broke up into a powdered substance inside of the ballistic gel.

The G2 Research RIP projectile is designed to fragment, regardless of the type of barrier it encounters. In this test, that holds true. When the RIP encountered bare gelatin, the trocars forming the outside of the projectile expanded like a flower, while the center mass of the projectile continued into the gel. With the addition of clothing, the RIP projectile performed almost identically as in bare gelatin, with the exception of penetration.

We noticed the SIG 9mm penetration numbers were pretty close. Upon inspection of the recovered bullet, it looks like the nose of the hollow point didn't get clogged and cause it to over-penetrate. We attribute this to the wizardry hidden in the projectile's Vshaped jacket skives and scores that allowed it to open, even when filled with dense fabric.

We spoke to a retired ammunition developer, who previously worked for the United States Army Special Operations Command for nearly five years, about the performance of these rounds. He said the FBI's standard for projectile penetration is 12 to 18 inches. Why a minimum of 12 inches?

Well, 12 inches is the minimum amount of penetration needed to reliably reach the vital organs that make the human body tick under varying conditions. Eighteen inches represents the maximum amount of desired penetration because, beyond that, all major organs are bypassed and the possibility for collateral damage becomes a greater concern. Generally speaking, .380 rounds are only expected to penetrate bare gelatin 6 to 9 inches, while 9mm rounds are designed to penetrate to the FBI standard of 12 to 18 inches.

Obviously, having a gun is better than having no gun, but there's no substitute for training and knowing what the potential legal ramifications are. In that case, caliber is moot. If your particular situation or body type doesn't allow you to carry a larger caliber pistol, then the .380 is better than nothing. Since the .380 doesn't generate as much energy or penetration in general as the 9mm, it's prudent to expect that it'll take greater accuracy or more rounds on target (or both) to have the desired effect. Shooting until the threat is no longer present, shot placement, the size of your opponent, and your caliber choice all play a part in the outcome of a deadly force encounter.