US Army researchers patent limited-range bullet to reduce chances of collateral damage

US Army researchers patent lim...
Diagram of the Limited range bullet
Diagram of the Limited range bullet
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Diagram of the Limited range bullet
Diagram of the Limited range bullet

Safer munitions may seem like a contradiction in terms, but modern designers put a lot of effort into creating weapons that do the least unintentional harm after or if they fail to do their job. A case in point is a new limited-range bullet invented by Brian Kim, Mark Minisi, and Stephen McFarlane at the US Army Armament Research, Development, and Engineering Center (ARDEC). Recently awarded a US patent, the proof-of-concept bullet disables itself after flying a preset distance.

Battlefields are already dangerous enough without stray rounds or other weapons endangering non-combatants, so the question of how to keep munitions from causing unintentional damage or injury is important to more responsible weapon engineers. Anti-aircraft shells, for example, are routinely fitted with fuses so they detonate before they fall to earth. In the same way, some types of sea mines and land mines are designed to deactivate after a period of time.

One area that has room for improvement is in smaller projectiles that have less of a chance of harming innocent people in combat. To achieve this, the new patented system uses a reactive material in the bullet that's ignited when the round is fired. This material burns in flight and at the desired range causes the round to become aerodynamically unstable. The range can also be adjusted for a particular mission.

Exactly how the system disables the round depends on what variant is used. In one version, the burning material distorts the round by melting its copper jacket until it starts to tumble and falls to the ground. In the other, the heat causes the round to disassemble into the base, center, and nose sections. As these fall apart, they also become unstable and drop.

The system was developed using computer models and simulations based on the .50 caliber M33 and the .50 caliber M8 rounds. The basic design was then refined so that the ballistics of the modified projectile would match or exceed the standard round out to the maximum effective range. Though the system was developed for the .50 caliber, the inventors say that it could be used on any projectile from 5.56 mm to 155 mm.

"The biggest advantage is reduced risk of collateral damage," says McFarlane. "In today's urban environments others could become significantly hurt or killed, especially by a round the size of a .50 caliber, if it goes too far."

Though funding for the development of the limited range bullet has run out, the engineers hope that the idea could find applications in later, safer munitions.

Source: US Army

How about a 'smart bullet' that recognizes transmitting sensors on friendlies that will 'self-destruct' incoming smart bullets fired from 'friendly fire' guns? In other words a bullet that won't hit it's mark if your on the side of good. If your Al Queda, etc no such luck!
This is an interesting reversal. Usually,they want better penetration of hard targets and body armor. Fragible bullets and hollow points would prevent over penetration but carrying more than one type of ammo would be difficult for changing conditions and would violate international agreements. Actually, the current 5.56 ammo penetrates less than the old .30 caliber ammo. When enemy combatants hide behind civilians or set up bases near schools and hospitals, collateral damage is unavoidable no matter how hard you try. We have no choice but to play by the same rules as the enemy.
it seems to me that the opposite style of bullet would be better; that is a bullet that won't kill until reaching a distance range. thus eliminating a lot of damage to your own comrades, who are close to you.
Patents do not apply to the military, in fact, if you try to patent something they like, they can even block and gag you and take your tech for free. Seems somewhat unfair that the same people with that power, who can never infringe patents at all, are allowed to obtain them; it would not surprise me if this fails to stand up in court.
Kevin Cloete
What if the bullet fails to function properly? That could do more harm then a normal bullet following its natural path. How often are people mistakenly killed because bullets went further than intended? Has any reliable study been done on collateral damage vs range/risk? Logically, it would seem the risk would decrease as the distance gets further. Who or what would be held responsible if something went wrong with a bullet like that?
A very interesting concept but it is unlikely to be compliant with International Humanitarian Law as it seems to contravene The Hague Declaration on Expanding Bullets, as well as Article 35(2) of additional Protocol 1 of the Geneva Convention. If this hits either a combatant or non-combatant at a point after the bullet expands this will produce some truly dreadful wounds that will be significantly worse than that produced by a conventional round that has not deformed. The design aims were laudable but I am uncertain how effective this will be at reducing "collateral damage" although it may assist in reducing the number of deaths associated with celebratory gunfire ie random firing into the air; what goes up must come down....somewhere!
Now all the crap we have seen about bullets starting a fire in movies will come true?
Douglas Bennett Rogers
A rubber or plastic bullet does this. Range might be too low. Maybe composite w. steel tip. Thought this would be expolding shell.
Maybe I'm not getting something important here, but when would such technology be used? I can't imagine it would be useful in today's urban scenarios. What, are you gonna equip your troops with bullets that only travel 20 feet? In open field scenarios, it's unlikely that civilians exist in high enough densities to warrant the use of ammunition that may not reach its intended target. Hey, if you're the bad guy, just back up your position enough so all the bullets hit the ground in front of you. Then all you have to do is stand up and take aim. Would soldiers be expected to carry short, medium, and long range ammo and switch in the heat of battle to the 'correct' distance rated cartridge? Would soldiers be held liable for accidentally shooting a civilian because he/she put in the wrong cartridge?
BS to get government funding. My father was an infantry veteran of two wars. He told me that one seldom if ever sees who he is shooting at. They simply shoot in the general direction of the enemy and hope to do the most damage, including damage done by ricochets which this bullet won't do much of.