Blue Line

News
Pistol-Calibre Carbines

The human body is amazing resilient and has evolved into a durable and complex system of physiological and psychological self-protection mechanisms. It is incredibly hard to stop when it doesn't want to be – and when it's bent on destroying you or someone else, no "magic bullet" will miraculously stop it with one shot.

Aside from a sniper shooting from a stable position, no bullet outside of a Hollywood movie will immediately incapacitate a goal-oriented human, bent on causing deadly harm, in a dynamic life-threatening situation. While many factors have been considered (and then discarded by experts) in the search for the elusive "one-shot stop," there are only two main scientific variables that directly relate to how quickly and efficiently an officer can stop a threat: shot placement and shot penetration.

Both can be somewhat controlled; one by good training and the other by good weapon and ammunition selection. After that, it is a matter of chance. Bullets do funny things in bodies.

November 15, 2013  By Dave Brown


The human body is amazing resilient and has evolved into a durable and complex system of physiological and psychological self-protection mechanisms. It is incredibly hard to stop when it doesn’t want to be – and when it’s bent on destroying you or someone else, no “magic bullet” will miraculously stop it with one shot.

Aside from a sniper shooting from a stable position, no bullet outside of a Hollywood movie will immediately incapacitate a goal-oriented human, bent on causing deadly harm, in a dynamic life-threatening situation. While many factors have been considered (and then discarded by experts) in the search for the elusive “one-shot stop,” there are only two main scientific variables that directly relate to how quickly and efficiently an officer can stop a threat: shot placement and shot penetration.

Both can be somewhat controlled; one by good training and the other by good weapon and ammunition selection. After that, it is a matter of chance. Bullets do funny things in bodies.

A pistol has one advantage; it is handy. It is not a rifle or shotgun, nor does it have the velocity to reliably penetrate deep enough to cause immediate incapacitation, but the best gun on the world is the one you have when you need it the most.

Advertisement

Shotguns extend the range for officers and can be reliably and accurately fired at intermediate ranges by almost anyone with some degree of good training. They require few fine motor skills and deliver a massive amount of firepower to the fight. The problem has always been that shotgun training has traditionally lagged behind the quality of handgun training. An entire generation of police officers don’t appreciate their advantages.

Now enter the patrol rifle. It extends a patrol officer’s response range even further and is both easy to shoot and reasonably accurate at intermediate to longer-range encounters. In ten years, I predict every Canadian officer will have quick access to a high magazine capacity semi-automatic rifle in his or her patrol car – but what about short-range encounters where you approach into shotgun and even handgun distances?

The problem with high-power rifles in an urban environment, critics say, is that they can go through the bad guy, plus two or three innocent bystanders.

Well… that’s not true and we are here to prove it.

The setup

This is not the first test to directly compare the penetrative capabilities of high-power rifles with pistol-calibre carbines, nor will it be the last. Test after test has shown that a patrol carbine chambered in either .223 Remington or 5.56mm and loaded with modern police ammunition is safer to shoot and more effective in terminal ballistics. So why do so many people still believe a high-power rifle will over-penetrate more than a pistol or even a similar rifle chambered for a pistol cartridge?

One reason may be that many people have seen the penetrative capability of a full metal jacket (FMJ) bullet, but law enforcement patrol rifles are not confined to the same Hague Convention on Rules of Warfare from 1907 as the military. Nor have ammunition and bullet manufacturers been sitting on their primers for the past 20 years.

So the premise of these tests was simple – to test the viability of pistol-calibre carbines against rifle-calibre carbines for patrol use in head-to-head penetration tests. If pistol-calibre carbines are to be acceptable or even preferred for patrol use, they must penetrate deep enough to incapacitate without causing undue hazard to others, and their shot must be more accurate than a handgun.

The questions

  • Will a pistol-calibre carbine improve penetration without putting others in greater harm?
  • Will a pistol-calbre carbine enhance shot placement capability over a handgun?

The tests

First, let’s have a moment of silence for the 60 or so water-filled milk jugs who gave up their lives for the benefit of scientific research.

While water jugs might not directly relate to more scientific tests using standardized ballistics gelatin, the numbers I recorded matched amazingly well with FBI test results.

Standard-issue tactical police rounds were first fired over a chronograph to determine muzzle velocity, then shot into a row of five water-filled milk jugs, six inches in depth, at common encounter distances to determine a base penetration depth. Once the base penetration was determined, we set up a stand with two milk jugs, a simulated wall with two layers of 5/8-inch drywall and a cardboard target, representing a bystander on the other side of a wall.

The exact same tests were done with a shotgun loaded with a standard police load of buckshot and slugs. The rifles were fired at typical encounter lengths, roughly the distance from the middle of an urban street to the side door of a house. The shotgun loaded with buckshot was fired the length of a short interior hallway and slugs at about the length of an average suburban yard.

The results

.223 Remington – The Federal Tactical TRU .223 round, loaded with the Sierra 55-grain hollow-point boat tail bullet, was fired from a Sako Varmint bolt action rifle with a 20-inch, 1-in-12 twist barrel, using the extraordinary Leupold Mark AR 1.5-4x20mm scope, suitable for everything from near-contact distance to 300 yards or more. Factory velocities are listed at 3220 feet per second and actual velocity on the test day was 3247 feet per second.

Initial penetration tests showed the .223 bullet made it through one full water jug and the first side of the second jug. Only fragments were recovered from the bottom. (Interestingly enough, this almost perfectly matches the 11.25-inches penetration into ballistics gelatin, as performed by the FBI. The recovered fragments looked exactly the same as those recovered in the FBI tests.)

When fired in the room simulation test at 20 yards, the .223 round was again stopped before it exited the second jug, leaving the drywall untouched.

9mm Luger – We used the Winchester Ranger SXT law enforcement round, loaded with a 147-grain hollow point bullet. Factory velocities are listed as 990 feet per second when fired from a 4 ½-inch barrel handgun.

The pistol-calibre carbine used was the new JR Carbine, manufactured by Just Right Carbines in Canandaigua, New York. Chambered for 9mm Luger, it was specially modified for target shooting with a Hogue overmoulded forend, Magpul CTR stock and EOTech holographic combat electronic sight. It uses Glock handgun magazines.

The SXT rounds chronographed at 1125 feet per second out of the 19-inch barrel, a considerable jump from the factory velocity out of a handgun barrel.

Initial penetration tests showed the 9mm hollow point round made it cleanly through three water-filled jugs and stopped just as it entered the fourth. The bullet was recovered in an almost textbook perfect expansion which again closely matched the FBI result in 16-inches into gelatin.

The interesting result was the room simulation. The 9mm SXT penetrated two water jugs and both layers of 5/8-inch drywall. It expended all its energy in the drywall, leaving only fragments and a dent on the front face of the cardboard target.

00-buckshot – Fired at five yards, penetrated two jugs, two layers of drywall and had enough energy left to send a bowling pin flying off the back of the stand. (When fired at the same distance as the rifle, it performed more like eight individual .33-calibre bullets, with most stopping in the first or second water jug.)

12-gauge slug – Slugs have the reputation of penetrating almost anything and this was proved in a dramatic fashion. At 12 yards, it punched all the way through five water-filled jugs, two layers of drywall and cleanly through a sixth water jug. It was never found.

(Just for the future reference of those politicians who would like to see a return to the military-issue FMJ 9mm, a test 125-grain full metal jacket bullet made it completely through three water-filled jugs, both layers of drywall and punched a clean hole through both sides of the ‘innocent’ cardboard target on the far side of the wall.)

The real world

There is no such thing as a free lunch. A bullet that penetrates enough to meet the FBI minimum criteria will penetrate walls and bystanders. The best backstop is hitting your target.

The bottom line – pistol-calbre carbines penetrate more than rifles but not as much as people think.

One of the problems with existing tests is that they seek to equalize factors that are never equal. In real life encounters, handguns might be considered seven yard defensive weapons. After that, accuracy falls off rapidly. Shotguns with buckshot can be effective out to 12 yards or more. Rifles are effective to 200 yards or more. (There are many factors that dictate the actual combat effectiveness of rifles, including the rifle, sight system, nature of the threat and the time available to defeat the threat.)

Shoulder-fired carbines are easier to shoot than handguns, increasing their hit potential. With modern electronic sights, they are potentially more accurate and develop higher velocities, which enhances terminal performance.

If an officer misses their intended target, a .223 will generally be safer to bystanders in an urban environment after passing through walls. Even at close range, they can be considered safer because of their fragility.

Other bullets will perform vastly differently, but with intelligent ammunition selection, .223 rounds on average will penetrate less than police-issue hollow point handgun rounds and can be considered safer for use even in close quarters in a rural or urban environment.

While pistol-calibre carbines may be initially tempting for extending the range over a handgun and for commonality of magazines, their potential for greater penetration may negate their suitability for many agencies.

Canada is quickly moving to a scenario where every armed officer will have access to a handgun on their side and a patrol carbine and shotgun in a car rack. Ammunition manufacturers are constantly updating law enforcement ammunition and the rounds used in this test are already seriously outdated.

So after all these exhaustive tests and a respectful burial of 60 dead milk jugs, which firearm would I choose?

That’s easy. The one in my hand when I need it the most.


Print this page

Advertisement

Stories continue below