Cartridge qualities

We are back to testing bullets again, and this time we are pounding Sig Sauer Elite Performance Ammunition into ballistic gelatin.

For this test, the goal was a little different. We wanted to see if the duty cartridge and its matching practice cartridge exhibited similar characteristics. Sig Sauer Inc., well-known for their reliable firearms, expanded their commitment to law enforcement and self-defense with their new cartridge products. Recently I began testing the Elite Performance Ammunition line. Then, in the middle of our testing, Sig Sauer Inc. introduced some centerfire FMJ cartridges designed to complement their SIG V-Crown Jacketed Hollow Point products.

The SIG FMJ pistol ammunition is now available in the following calibers and bullet weights: 100-grain .380Auto, 115-grain 9mm Luger, 124-grain .357SIG, 180-grain .40S&W, 180-grain 10mm and 2300-grain .45Auto. Years ago, it was found that hollow point cartridges are more efficient. The rapid expansion in any media increases the rate of energy transfer in a given amount of time and space. Cartridge design has to include the intended use of the cartridge and other factors that weigh heavily into the agencies’ selection of a cartridge.

Readers email me all the time with the same question: “What’s the best cartridge for…” First, I love answering reader questions. However, I will always explain that agencies have to look at several factors. These factors include reliability, accuracy and terminal performance. These factors are conditioned by other secondary factors, which include felt recoil, muzzle flash, clean burning, and specific factors concerning the intended firearm. One specific factor included a couple of (off-brand) .380 Auto cartridges that were available a few years ago that had a heavier projectile, and therefore a longer case length. They delivered great performance, but did not chamber correctly in one of my test guns.

I’ll ask, “What are you planning to do with the cartridge?” This is not a silly question. Reliability, accuracy and terminal performance factors vary, and often a cartridge is strong in one factor, and average in another. For example, what if your agency generally carried handguns concealed and, if called upon to use them, the likely scenario would be a longer shot than what would be considered generally prudent for a handgun? That’s exactly what many protection detail assignments require. For such an assignment, accuracy has a higher priority. Some cartridges perform better “after barrier” or after the bullet strikes something solid. The impact can disrupt the jacket, veer the bullet off course or separate the jacket from the core. Some cartridges don’t have the requisite velocity to continue through the target 12 to 18 inches.

What we are really asking is whether a cartridge has first shot effectiveness. That is, will it prevent further attempts of violence after the first shot? Granted, we don’t train for single shot encounters, nor is there a statistical reason why we should. But we want to know that each individual shot has the most amount of effectiveness. This is not really predictable, but cartridge capabilities can be predicted hypothetically, assuming all other factors are equal in a given situation.

What we know

A cartridge may have great velocity and accuracy, yet marginal terminal performance. Worse, its design could cause it to over-penetrate or the bullet jacket could separate from the core. A cartridge that performs well in bare gelatin may not do as well in after barrier tests. Conversely, a good “after barrier” performer may be marginal in bare gelatin. We consider some cartridges ineffective for law enforcement. These include .22LR, .32 Auto and similar cartridges. They are ineffective because they don’t provide enough penetration, energy transfer or user confidence for duty use. Other cartridges are impractical because they go beyond the design parameters of a handgun, or require an unreasonable skill level.

Most people know the common cartridges effective for law enforcement. They are 9mm, .357 SIG, .40 S&W 10mm, and .45 Auto.

We know that in bare gelatin some cartridges perform very well. That is, they continue through the testing media 12 to 18 inches without separation of the core and the bullet jacket, with adequate expansion. This performance must be consistent and repeatable. Some bare gelatin performers do poorly when a few layers of fabric are placed in front of the gelatin. That is, the fibers become impacted in the hollow points and they behave like a solid point bullet. This means that they over-penetrate, which translates to poor terminal performance and an increased danger to the officer and the general public.
If the cartridge is not reliable, all bets are off. Duty cartridges should be tested at night for muzzle flash in the intended firearm.

We never recommend that agencies purchase a product that has a “liability magnet” name, regardless of its effectiveness. Presenting the “Punishment Pill”, “Death Deliverer”, or similarly named product in civil court is implied consent for entrance in the lawsuit lottery.

Lindsey’s Three Rules of Cartridge Performance have not changed:

1. Shot Placement.
2. Shot Placement and
3. Shot Placement.

These rules make any duty cartridge the best duty cartridge available.

The SIG V-Crown Jacketed Hollow Point uses a deliberate design that looks like a conventional hollow point but expands reliably in media, regardless of the presence of fibers. They call this a “stacked hollow point” and the point is like a crater with a center channel. The SIG V-Crown bullets have a relatively high cannelure, or a groove crimped into the jacket. It is ordinarily used as an area where the brass is squeezed in to hold the bullet in the cartridge a bit firmer. This cannelure was designed to keep the lead affixed to the jacket under the strain of travelling through media. All of the duty cartridges are coated with DUCTA-BRIGHT 7A, which adds reliability and corrosion resistance. In all of the testing we have done with Sig Sauer cartridges, which includes several sessions since they have been on the market, there’s not been one single reliability issue.

Sig went with hard jackets and V-shaped jacket skives and scores in their hollow point bullets. This is new technology in the bullet industry, and definitely a step up in reliability. Here’s how it works: In the auto industry, several car manufacturers have pre-scored or pre-engineered areas on the body and frame of the vehicle designed to crumple predictably in an impact. When the vehicle is in a head-on collision, these areas collapse first in a prescribed pattern. Although it would appear to the outside observer that the vehicle gets completely demolished in a head-on collision, the passenger compartment remains intact. In the auto and rail industry this is called controlled deformation or “crush zones”.

We don’t call this engineering by the same name in cartridge manufacture, but it basically does the same thing. First, these skives and scores allow a bullet to open at a controlled rate in media, but they prevent the bullet from over-expanding or shedding its jacket. The best way to prove that this engineering design works is to fire the bullet into ballistic gelatin and compare its performance in ballistic gelatin after it breaches a solid barrier. In the case of bullet testing, the solid barrier is basically windshield glass set at an oblique angle to the path of the bullet.

The matched pair in .380 Auto consisted of a 90-grain Sig V-Crown plus a 100-grain FMJ. We used our Bersa Firestorm .380 and shot blocks of Clear Ballistics gelatin. The 10-grain difference was not noticeable and the bullets printed similar targets downrange. Although the hollow point version did not make 12 inches of penetration after barrier, it certainly performed better than most .380 cartridges. The 90-grain projectile reached a consistent 9 inches in gelatin after barrier and 9.5 inches in bare gelatin. Expansion was about 130 percent and weight retention was 100 percent.

This begs the question, “Is .380 Auto a viable option for off duty or backup?” The answer is that it is still an option but officers need to know that there are inherent limitations. However, the tradeoff is the compact guns that shoot the .380 and the fact that they are easy to shoot quickly and accurately. Our readers have already seen the great performance of the Bersa Firestorm in the July 2015 issue and the Sig V-Crown worked well in it, too.

The 9mm 124-grain bullet penetrated 13 to 14 inches after barrier, although one round left the block after 10 inches. The bullet exhibited 100 percent weight retention in the block. The 115-grain Sig V-Crown stayed around 12 to 13 inches with excellent expansion-between 150 to 155 percent. The 115-grain cartridges felt “lighter” in perceived recoil. The 115-grain FMJ and 115-grain Sig V-Crown cartridges felt and behaved almost exactly the same in our test guns. This is a perfect matched pair for training and duty.

The .357 SIG V-Crown cartridge launches a 125-grain bullet at very respectable velocities ranging from 1,300 to 1,370 fps. The bullet diameter is the same as a 9mm, but the significant increase in velocity changes everything.

The .367 SIG is a great cartridge to demonstrate some of the unusual findings we come across when we do ballistic gelatin testing. In bare gelatin, the hollow cavity and pre scored petals open quickly, causing a braking effect that is abrupt. It’s easy to see when looking at the block from the side. The thicker cavity created by an expanded bullet begins early in the block. In bare gelatin, the .357 Sig averages about 13.5 inches of travel. When we fire into clothing material (we use denim layers), the impacted fibers don’t allow the bullet to open quite as quickly. This is where the unique bullet design showcases its engineering. Fired through fibers, the bullet averages about 14.25 inches.

The .357 Sig bullet fights to hold onto its jacket when fired through laminated glass. The glass is instantly pulverized into powder in the hollow point, causing it to momentarily behave like a hollow point. In the first 3 to 4 inches the bullet remains at 100 percent of its diameter, until it begins to expand. Surprisingly, the bullet travels a full 16 inches in the block before it comes to rest, fully expanded to 150 percent of its diameter. Often, the bullets are not facing completely forward at their point of rest.
In the .357 SIG, a couple of bullets partially shed their jackets. This behavior would be a concern in some cases, but this happened after 16 inches of penetration and the jacket only continued to 17 inches. After barrier, this is still good performance.

Of the practice FMJ/duty Sig V-Crown combinations we tested, the .357 SIG ones matched the best, delivering almost exactly the same sub 3-inch groups downrange.
The .40 S&W combination was rather boring. Bare gelatin and after barrier hovered around 12.5 inches. The bullets expanded as prescribed, even while we used a short barrel S&W M&P Shield for a test gun. It grouped well, but did not distinguish itself from any other 40-caliber products.

Although Sig Sauer makes their .45 Auto in three different weights, the 185-grain cartridge delivered the most dramatic performance. It consistently opened up to 150 percent in after barrier tests, coming to rest at an average of 16.5 inches, with 100 percent bullet weight retention. This bullet left a trail of glass powder down the gelatin cavity.

Finally, we need to boast about the performance of the .45 Auto 185-grain Sig V-Crown performance. Although the practice bullet weighs 230 grains, they both printed similar targets downrange and the “felt” recoil impulse was similar. We were able to group around 3.5 inches off hand at 20 yards pretty consistently. That is pretty good duty/practice combination.

The current trend is to create a close match between the training and high performance duty cartridge. Sig Sauer has raised the bar with this ammunition.