Moving Beyond Brass and Mushrooms: Full-Stop is the 21st Century’s 9mm

By Art Merrill

Welcome to the future

This is not just another story about the latest and greatest pistol ammo—this one begins with a shootout on April 11, 1986 that changed the worlds of law enforcement and pistol combat. On that day in Miami, Florida, a walking dead man murdered two FBI agents after being shot with a 9mm Luger bullet before finally succumbing to his “non-survivable wound.” The incident prompted the FBI to abandon the 9mm cartridge.

A very long story shortened to one sentence, the FBI’s search for a suitable replacement for the 9mm Luger culminated in the introduction of the .40 S&W cartridge, subsequently adopted almost universally by LE agencies all over the U.S. and by many citizens who choose to carry a handgun for self-defense.

So why, after all that effort and the passage of three decades, is the FBI putting the 9mm back into agents’ holsters? Because advancements in bullet and cartridge technology have made the 9mm viable once again. Two striking advancements that you may not know of have fundamentally changed bullet and case performance, and together they are the first to move ammunition out of the 20th Century and into the 21st.

A +P Hole Saw?

L-Tech, an ammunition manufacturer and ballistic test facility in Eubank, KY, has been quietly providing its services to the U.S. military and to LE, as well as manufacturing Sig Sauer’s ammo products since 2013. After following FBI penetration test protocols, L-Tech has now released its unusual-looking, but high-performance, 9mm Full-Stop ammunition to the public.

Full-Stop is not simply an expanding bullet launched at +P velocity—it is an entirely new 9mm Luger cartridge created from mating a remarkable, two-piece case with a bullet that behaves pretty much like a flying hole saw or blades from a food blender. And here’s the kicker: the maker says the cartridge produces, with apparent disregard of physics, +P velocity without producing +P pressures.

Mostly Hollow

The Full-Stop 124-grain bullet doesn’t expand in the traditional sense of forming a “mushroom” pushed by a solid base. Instead, after about 1.5 inches of penetration into a soft target the Full-Stop bullet nose opens up into a three-bladed “propeller,” as the maker calls it, that chews its way through tissue at high velocity to create maximum trauma.

“The Full-Stop creates a wound channel about two and a half times that of a standard hollow point ‘mushrooming’ bullet,” said L-Tech president Larry Henderson.

The bullet has no core. It is instead a homogeneous copper alloy, like a premium lead-free expanding hunting bullet. Disassembly at the loading bench showed that half of the Full-Stop bullet’s length is essentially a hollow point, and its three expanding sections, which are joined at the apex, are clearly evident. A long ogive and small hollow point opening lend the bullet the appearance of a long, tapering nose. The bullet base has a typical slight bevel to facilitate seating.

Because much of the bullet is hollow and it is mid-weight for the caliber, without any (weighty) lead, it must be made longer to achieve 124 grains. Therefore, a good portion of it nestles into the case. An inertia bullet puller required no undue force to remove bullets, indicating a normal crimp, and subsequent examination of the bullet surface showed that factory crimping of the stainless-steel case does not unduly deform the copper bullet.

Wait—did I say, “Stainless steel?”

A Case for Stainless

The cartridge case is the new NAS3 (Nickel Alloy Steel) developed and marketed by Shell Shock Technologies (SST) in Westport, CT, made by mechanically bonding a nickel alloy case head to a stainless-steel cylinder. SST says its NAS3 case is superior to brass, as it is cheaper, stronger and lighter, and as it possesses a greater internal volume, as well as a beveled and enlarged flash hole. The case head can be color anodized for instant ID and you can pick up your fired cases with a magnet. The empty cases are available to handloaders and can be reloaded 40 or more times without trimming, though they require special proprietary dies from SST. Reloading using standard shell holders will weaken the NAS3 case body-to-head bond, possibly resulting in case separation upon firing or extraction. DO NOT ATTEMPT TO RELOAD NAS3 CASES USING STANDARD DIES.

FBI Protocol

Full-Stop’s performance is almost identical to that of the FBI’s benchmark Speer 124-grain Gold Dot load. The FBI testing protocol is to shoot through real life barriers at real life distances that law enforcement may encounter, into ballistic gelatin. Bullets are then examined for penetration and expansion. Barriers include clothing, wood, dry wall and sheet steel (simulating a car door).

SAAMI standard maximum pressure for the 9mm Luger is 35,000 psi; for 9mm +P, it’s 38,500 psi, or a 10 percent increase over standard. A perusal of various factory load data shows that, with 124-grain bullets, the velocity for 9mm +P begins at about 1,200 feet per second. Full-Stop gel penetration after passing through some barriers exceeds that of the +P Speer ammo, and yet the L-Tech is not loaded to Speer’s +P pressures, according to company literature. Newton says that less pressure equates to less recoil and, at least theoretically, that implies a faster on-target double-tap. SST, incidentally, has tested its NAS3 cases beyond 65,000 psi, so the upper limits of safety regarding pressures rest with the handgun and not the cartridge case.

At the Bench

Dismantling a few cases for examination revealed bullets weighing about 124.5 grains, seated over a 4.8-grain charge of spherical powder that resembles W231 or Titegroup. The inertia bullet puller caused a slight but visible separation of the case body from the case head. Another note to handloaders: don’t reload NAS3 cases after pulling bullets, discard them.

Frankly, any ballistic testing I might have done to check L-Tech’s claims for Full-Stop’s bullet expansion and penetration would, at best, only be duplicating the FBI protocol testing, and there’s no sense in reinventing that wheel. However, we can objectively test for accuracy, velocity and functioning, and we can form a subjective opinion of recoil. So, let’s take a couple of 9s to the range and see what we get.

Range Test

Since the L-Tech is defensive ammo, it seemed appropriate to shoot it in both full-size and compact carry pistols, the former a Ruger American with a 4-inch barrel and the latter a 3.5-inch barreled S&W M&P Shield. Checking accuracy at handgun combat distance—21 feet—is being realistic, too.

In both handguns, L-tech’s ammo shot essentially to point-of-aim, a six o’clock hold on a black bullseye target, with 10-shot groups hovering just under two inches when utilizing a steadying forearms-on-the-shooting-bench hold. Groups from the Ruger were only an inch wide but tended to string vertically a bit. The S&W made a more amenable match with the ammo, generally grouping shots into a single ragged hole without a propensity for stringing. Most importantly, those long, tapered bullet noses fed reliably, and both guns functioned flawlessly with the L-Tech ammo—an absolute, no compromise “must” in a defensive handgun.

Velocities 10 feet from the muzzle of the Ruger averaged 1,090 feet per second with a low of 1059 feet per second and a high of 1,111 feet per second. As expected from a shorter barrel, velocities in the S&W dropped a bit: the slowest at 973 feet per second and the fastest at 1,031 feet per second, for an average of 1,010 feet per second. Subjectively, recoil seemed ordinary, and of course a bit sharp in the compact Shield with a shortened grip that I could only hold with two fingers.

Because the NAS3 cases weigh half as much as brass cases, a full high-capacity magazine also weighs less, on the belt and in the handgun. I didn’t detect any discernible difference in weight when gun handling, though it is obvious when you hold a few of the NAS3 cases in your hand. Roughly, empty brass 9mm cases weigh 60 grains and NAS3 cases, 30 grains. Multiply that by 15 rounds in a mag and we find one stuffed with the L-tech cartridge weighs 450 grains—about one ounce—less than a mag holding regular brass.

Back from the Grave

So, what’s the takeaway? For handloaders who shoot a lot of 9mm, the new case represents significant cost savings. Forty reloadings are anywhere from three to five times—or more—than what we’d get from brass, especially with maximum loads, and we can add to that a lower initial cost than new brass. The cost of the specialty dies ($100) is amortized over time and the number of reloadings.

For competitors and those of us who practice a lot, picking up cases with a long-handled magnet is a convenience, as is color coding our own cases. Achieving +P velocity without +P pressure means we get the highest performance without sending handguns into early retirement from the battering. And we lighten our range bags when ammo weighs less.

For serious defensive work, we’ve seen a lot of new self-defense pistol bullets hit the market in the past few years, a trend that continues as bullet technology advances. Technology, in fact, has brought the 9mm Luger back from law enforcement’s common grave that it shared with the .38 Special. “A couple of law enforcement agencies here in Kentucky have adopted Full-Stop as their duty ammo,” Henderson said.

Even the .380 ACP has improved beyond a better-than-a-sharp-stick choice. The Holy Grail, of course, is the immediate incapacitation of the One Shot Stop, but like the Arthurian Holy Grail, it is elusive and not attainable via technology alone. There is no substitute for proper bullet placement, and then the bullet has to perform optimally when it gets there. The first step is up to you; if you succeed, it appears L-Tech’s Full-Stop bullet will do the rest.

Art Merrill graduated from the FBI Firearms Instructor Development Course to teach U.S. Navy security force personnel pistol and shotgun combat tactics.