Smashing down doors might seem like a pretty low-tech job, requiring little more than brute force and attitude. But in reality, there's a lot more to it than that. Experience in Iraq and Afghanistan is resulting in some new and sophisticated door blasters with magnetic bullets, "liquid solids" and other exotic technologies being deployed.
Today, the Army's preferred method for breaking down doors is "a 12-gauge shotgun, loaded with buckshot or slugs," as the Army's field manual on urban combat skills notes. But there's a big drawback to that method: collateral damage -- not just to the people on the other side of the door, but because of spatter from shot ricocheting back into the breaching team.
This hazard led to demands for something safer, like this Urgent Request for 25,000 special breaching rounds from the Marine Corps in September '06 which specifies "a lead-free projectile cartridge with a frangible 40 grams steel powder/wax payload. The frangible slug disintegrates into a powder upon impact producing no shrapnel." This type of round has been known in civilian circles for some time, and in June last year it was finally type classified for military use as the M1030. The new ammunition means there is no risk of spatter; the announcement indicated that "Soldiers have suffered severe injuries during breaching operations utilizing buckshot cartridges," and mentioned that "The requirement for a munition like the M1030 was identified by the Army in 1997." It seems that it took eleven years and a war for the special rounds to get into the hands of soldiers.
However, the powder ammunition could use some improvement. Mechanical Solutions Inc. has an intriguing solution: magnets.
The company has designed a new type of door-breaching ammunition for Special Operations Command. It uses powder that's held together into a solid projectile by a series of small magnets after firing -- but disintegrates on impact, "removing targeted door hardware." The company claims the magnetic technique is more effective than holding the slug together with wax or other binders – presumably because the attraction can be turned off instantly. I'm guessing there are some clever electromagnets involved; Mechanical Solutions won't discuss the ammunition.
Special Forces also funded the development of another technology by Polyshok Inc., known as the Impact Reactive Projectile. The firm says this 12-gauge ammunition solid slug acts as a liquid. Unlike other projectiles, it will not over penetrate and go through walls. It pretty much stops where it hits - and causes gigantic injuries in the process.
The Polyshok breaching round development cost almost two million dollars. The key is an actuator, which on impact "directs the spherical lead powder core into a radial dispersion pattern" at right angles to the direction of the impact. Within milliseconds there are 14,000 tiny lead particles expanding outwards producing an extremely powerful shockwave. The concept is not entirely dissimilar to the Dense Inert Metal Explosive used for "low collateral damage" bombs intended to produce maximum impact in a minimum area.
Shotgun breaching rounds are fired from point-blank range -- there are special barrels available to facilitate this. But sometimes you may want to open the door from some distance away. In 2007, Israeli arms-maker Rafael introduced their Simon door-breaching grenade, which was promptly adopted by the U.S, as the M100 Grenade Rifle Entry Munition (GREM). It's an old-fashioned rifle grenade, fired from the end of any assault rifle at a range between fifteen and a hundred meters. A special stand-off detonator and quarter-pound explosive charge ensure that it knocks down most doors.
There are two issues with the GREM: one is that it looks a lot like the Rifle Launched Entry Munition, which the U.S. Army was looking at back in 2000 (also a Rafael design) -- again it seems to have taken seven years and a war to get it delivered.
The other issue is that the blast is still pretty ferocious and you have to be fifty feet back to be safe. The Army is looking to solve this with the help of Frank Dindl, an ammo developer working on a new model of focused-blast device. It's designed to have an expanding explosive warhead which reshapes itself on contact with the target. Phase II development will not be completed until the end of this year, so it might be another year or two after that before the final product is ready. By which time it may not even be needed, or at least not until the next war.
Knocking down doors may seem a crude business. But the technology still takes years to perfect.
[Photo: U.S. Marine Corps]
