The “Bolo” Shell
Advanced Ballistic Concepts’
Multiple Impact Bullet.
Looking ever so much like the shell for a 16-inch naval gun, the Advanced Ballistic Concepts’ Multiple Impact Bullet for 12-gauge shotguns is an intriguing and impressive-looking projectile. In fact, when I viewed the initial video of its deployment downrange, I couldn’t believe what I was seeing was in the realm of ballistic possibility.
Making the observation that 95 percent or so of civilian gun battles occur at less than 21 feet and 93 percent of first shots are misses, Advanced Ballistic Concepts designed their pre-fragmented Mi-4 bullet to separate rapidly into four projectiles upon leaving the muzzle of a rifled shotgun barrel or rifled choke tube. What’s very unique and different about the Mi-4 bullet is the three interlocking segments forming the body of the little shell and giving it its shape are tethered to each other by Kevlar strings as they fly downrange, 120-degrees apart.
Think of a South American bolo. This is a 12-gauge bolo shot with three pieces of tethered shrapnel and a bullet. According to the makers, the three segments, of equal size and weight, open up into a stable circular pattern, rotating downrange with a diameter of 24 inches before reaching a distance of 21 feet, while the detached nose slug bores straight ahead. That’s where the digit “4” comes from in the Mi-4 moniker—four projectiles slamming downrange with a pattern much larger than a conventional load of buckshot could deliver at that range.
By changing the composition of the metal used to form the bullet and its muzzle velocity, Advanced Ballistics Concepts states they have designed both a lethal and a less-than-lethal Mi-4 projectile. The four parts of the lethal design are made of lead for maximum penetration, while the less-than-lethal slug is composed of a lightweight zinc/copper alloy with a lower muzzle velocity to minimize penetration and collateral damage; but keep in mind, even less-than-lethal ammunition can kill. Both slugs are described as bore-safe in 12-gauge tubes.
This toughlooking fellow absorbed two hits, and if his chest was an inch
or two bigger, he would have been smacked by all four..
Recovered segments show only minor deformation.
While the Mi-4 can be fired in a smoothbore, the results will be inconsistent. The interlocking segments system of the Mi-4 needs the centrifugal force imparted by a rifled shotgun barrel or rifled choke tube to separate the projectiles, accelerate expansion and maintain accuracy.
I was really curious about this slug. Would it open up to 24 inches in 21 feet as the maker claimed? How would a load of No. 4 buck perform at the same range? Would the terminal ballistics of the inefficient-looking projectiles appear to be effective? What would happen if just one piece of the tethered shrapnel hit the target or an obstruction like the edge of a wall or a piece of furniture? Would the bolo pattern collapse and the total shot be compromised?
For precision in testing, I selected a scope-sighted, rifled Savage shotgun rather than a rifled choke tube. For a unique round, you need a challenging target. Our challenging choice was zombies, in both paper silhouettes and a battle hardened, 2-dimensional guy, courtesy of Zombie Industries, the leading zombie emporium. Since I only had five rounds of each type of bullet, I started with the non-lethal round just to get a feel for new ammunition.
At 21 feet, the non-lethal bolo pattern was perfectly centered on the first zombie with a diameter of 24 inches and with the nose slug impacting at the point-of-aim. I was impressed. The round did exactly what the makers said it would. It made four hits, and the connecting strings sliced that target into three equal 120-degree pie sections. I found the remains of the strings just in back of the paper. One bullet segment had hit the dirt behind the target and ricocheted 90 degrees to the left and landed about 30 feet from the target, where it was later accidentally discovered.
Advanced Ballistic Concepts currently offers both lethal and semi-lethal ammunition.
The complex structure of the Mi-4 bullet is incredible. Notice the spooled thread
(far left) holding the three petals together.
As fired, this is what the Mi-4 looks like as it extends.
Next was the lethal lead projectile at 21 feet. The bolo pattern was again centered on target, with a diameter of 24 inches and with the nose slug impacting at dead center. To compare those results with a 2-3/4-inch load of No. 4 buck, I grabbed my open-sighted cylinder bore Century International Arms Model 87 shell shucker and let fly with a standard Federal load of 34 pellets of .24-caliber No. 4 buck. The No. 4 buck shot at 21 feet produced a small, square 5×5-inch pattern. No comparison.
Next came our foam-filled, plastic, battle-hardened zombie. At 21 feet from the Savage slug gun, the Mi-4 round scored two hits—the centered nose slug and one piece of shrapnel I’m pointing to in the photo. The nose slug passed through 4 inches of foam and the 1×2-inch mounting stake behind the mannequin. The other two projectile segments just scraped some paint off the left and right edges of the zombie’s chest (he’s a small chested guy). Those results lead me to believe if only one piece of shrapnel hits the target, the integrity of the bolo pattern is maintained.
Searching the dirt behind the targets, I turned up two more pieces of shrapnel and a nose slug lying on top of the ground. They looked like they could be reloaded.
Conclusions? I’m not ready to give up my buckshot yet, but as the first round down the tube, the Multiple Impact Bullet may have some invaluable applications. It would be interesting to view a series of ballistic gelatin tests made by the company to determine exactly what these odd looking projectiles do at impact and how far they penetrate at different shooting distances.
Advanced Ballistic Concepts’ interesting website mentions 10 inches of penetration for the three bullet segments, creating crescent shaped wound paths, and 14-inch penetration for the center nose slugs, but unfortunately, the distance-to-target is not specified. When I look at the shape of the holes in the paper targets, some of the segments hit flat on, leaving a complete body profile, while others seem to punch through the paper point-of-base first. The maximum effective range of the round would be an interesting question for the company to address as well.
Zombie No. 2 took a perfectly centered hit with the detached slug as well as the tethered segments.
Advanced Ballistic Concepts is currently marketing both lethal and semi-lethal 12-gauge and .45 ACP ammunition (9mm pending). A 10-round pack of 12-gauge is currently selling for approximately $60 and .45 ACP for $50. They also offer a complete line of 1:35-inch twist rifled choke tubes for every brand of shotgun.
I guess what surprised me the most is this complex, multi-projectile round actually worked and, not only worked, but performed exactly the way Todd Kuchman, President of Advanced Ballistic Concepts, said it would. It’s a remarkable invention. Zombies, beware!
By Holt Bodinson
Photos Ilse Bodinson
Advanced Ballistic Concepts, LLC
8 Columbine Lane
Littleton, CO 80123
12925 Bookprinter Place, Ste.200
Poway, CA 92064
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