Army Engineers Patent ‘Limited Range’ 50-Cal Bullet

Patenet diagram of self-destructing bullet

The Shooter’s Log readers may find it hard to believe, but three U.S. Army engineers have received a patent for a bullet that will become “aerodynamically unstable” after flying a certain distance.

Awarded U.S. patent 9,121,679 B1, the limited-range-projectile bullet is equipped with a reactive material that will ignite when the bullet is fired and burn during flight, causing the bullet to become aerodynamically unstable.
Awarded U.S. patent 9,121,679 B1, the limited-range-projectile bullet is equipped with a reactive material that will ignite when the bullet is fired and burn during flight, causing the bullet to become aerodynamically unstable.

A proof-of-concept bullet developed by the U.S. Army will disable after flying a certain distance, helping to prevent injuries from stray rounds.

Recently awarded U.S. patent 9,121,679 B1, the bullet is equipped with a reactive material that will ignite when the bullet is fired and burn during flight, causing the bullet to become aerodynamically unstable at the desired range.

Brian Kim, Mark Minisi, and Stephen McFarlane filed collectively for the patent on May 7, 2013 and were notified of its approval on Sept. 1, 2015.

“We wanted to protect the U.S. government’s interests and position,” McFarlane said. “The biggest advantage is reduced risk of collateral damage. 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.” The concept for the limited range projectile includes pyrotechnic and reactive material. The pyrotechnic material is ignited at projectile launch. The pyrotechnic material ignites the reactive material, and if the projectile reaches a maximum desired range prior to impact with a target, the ignited reactive material makes the projectile aerodynamically unstable.

The original idea was intended to apply to .50 caliber ammunition. However, the patent covers the idea and technology, so it could theoretically be used in various small arms munitions.
The concept for the limited range projectile came to fruition when the small caliber ammo development team was funded to investigate the feasibility of a pyrotechnically actuated disassembling limited range .50 caliber bullet.

“It was essentially my idea to create a self-destructing small caliber round akin to the larger caliber ones,” Minisi said. “The type of reactive materials to use and how to test it was Steve’s idea.

“Brian was instrumental with executing the effort, particularly the modeling and simulation to confirm the concept,” he said.

Currently, funding for the project has ceased. However, engineers hope their concept will resurface as the constant need to provide greater technology for the warfighter increases.

Kim, Minisi, and McFarlane are employees of the U.S. Army Armament Research, Development and Engineering Center (ARDEC) based at Picatinny Arsenal, N.J.

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Comments (25)

  1. FOX News, Really needs to do Better Fact Checking! As of 18 February 2016, according to US. 162556, the .50-Caliber Limited Range is STILL In Production. And is Currently being use by AT LEAST “THREE” NATO Armies.

    A Prototype .50-caliber Lightweight Machine Gun, WAS CANCELLED…

  2. You do realize that this is in response to Obama’s demands for “safer” military weapons. Not a judgement, just a fact from someone who has been working USG contracts since 2004.

    All well and good, but why are we limiting the effectiveness of our soldier’s weapons for any reason? When I was in Afghanistan, the troops there were forbidden to use their M203 grenade launchers because they might do too much damage, and air strikes and arty support were strictly controlled.

    I understand not wanting to harm civies, and I had Iraqi friends when I was there who I worried about, but I worry a lot more about our troops and the way we are hamstringing them for the sake of PC philosophy. If we are going to send young Americans into harm’s way, we should not limit the weapons they are authorized to use in defense of their own lives. Otherwise, do not send our troops to war in faraway places unless you are going to allow them to fight with everything they have to survive.

    Now, if anyone out there wants to flame me for this outlook, feel free. But before you do so, please share with us all how many times you have been IED’d, shot at, or had a friend captured and tortured to death and I will do the same with you.

    1. @ Milial.

      Which Restriction is That, Sir. The “Only” One that I’m aware of is the 13 February 2003, Restriction on Sale of M203 40mm Grenade Launchers to Public Sales too Civilian Use…

    2. @Secundius

      I don’t understand what you are asking. I didn’t mention any “restriction” or anything regarding the use of military weapons by civilians.

      My comment had strictly to do with ROE for troops in conflict zones that forbade them from using all weapons at their disposal in combat. When Karzai was in power he regularly pitched a fit about US troops and collateral damage, many of which were fabricated incidents. Consequently there were several occasions where US troops were ordered not to use the M203 and Mk19 launchers in built up areas or areas where there may be civies. Consequently, they were subjected to heavy Taliban fire under circumstances that made it very difficult to suppress the enemy because they couldn’t use an area weapon against them.

      My other reference was to Obama’s Executive Order of January 4, 2016 in which he instructed the military to seek out and develop “safer” weapons for the troops. It’s discussed in multiple articles. I’ve included a link for you below, but it’s also easy to find simply by Googling it.

    3. @ Mikial.

      The Obama restriction is NOT on the Military. But Usage to Law Enforcement Agencies, Like Local Police Departments…

    4. Secundius, what are you talking about?

      Both the article we’re commenting on and the one I sent you the link to specify it is the military Obama has directed to find safer weapons, not the police. Do you even read the articles?

  3. In response to Musicman44mag.
    The enemy does not need to stand still or stay in one place. The projectile will next be designed to seek out the enemy and destroy the intended target no matter where they hide or how fast they move thus; permitting us to remain secured in a safe position and out of harms way and if anyone is interested I have a bridge to sell.

  4. This is really an insane idea. There might be special situations where this kind of munition would be appropriate; however, this is another silly project that not only costs tax money for development but also will significantly drive up the cost of ammo… that is if the politicians use this to drastically affect the ability of gun owners to choose what they feel is right for their self-protection situation. The cost of an outrageous project such this greatly outweighs the benefit. Some people don’t have enough to do.

  5. This idea doesn’t make any sense. The “timed” explosion cannot predict when the target has been hit. Why not make it explode on impact????

    Plus, if they use 50 caliber, chances are it will pass through the target before exploding.

    And all this 50 cal stuff is supposed to be going on in URBAN areas?

    What were these goof balls thinking? Do Army Engineers have real engineering degrees or what?

    1. @ ss1.

      There is an 18th century Terminology for the Round, which called a “Floorer”. What it Does is Expend ALL of it’s Kinetic Energy at Close Range, without “Over Penetration”. In Boxing Parley, a “KO” (Knock Out Blow). Like the .50 Beowulf or the .458 WinMag, or a .50BMG “Boattail” Round or .50BMG “Dum Dum” (Hollow Point)…

    2. @Secundius:

      Yes everyone wants a knockout blow, but a good hollow point will have that explosive punch. The ammo mentioned in this article explodes all by itself as a timed event, unless I’m reading this wrong. It needs to explode on impact, as I’m sure many missiles do in modern warfare.

    3. @ ss1.

      An “Impact Detonation Fuse”, What Of It. It’s NOT Like there going to be In General Circulation for General Public Usage…

    4. @Secundius:

      Here is a quote from this article: “the bullet is equipped with a reactive material that will ignite when the bullet is fired and burn during flight”

      It’s the “during flight” concept that I think is nonsense.

    5. @ ss1.

      So the Projectile “Self’s Destructs” at a Predetermined Range.

      Keep in Mind that a Record was set using a Barrel M107 Sniper Rifle with 29-inch Barrel. In 29 April 2009 of ~6,912-meters Near Flat Trajectory Range, That’s nearly 4 & 1/4-miles. I can’t Think of ANY Outdoor Ranges (other than Big Sandy) and the Military Artillery Ranges. That 5+ Miles of Straight Line Shooting, CAN YOU…

    6. @Secundius

      We’re not talking about civilian applications here, we’re talking about military applications. The size of the largest outdoor range is irrelevant. Our war fighters should not be limited in any way. Period.

    7. @ Mikial.

      A 12.7x99mmR/BMG Projectile will Punch a Hole through ~2-inches of Steel Plate Armor at 1,000-meters (Point Blank Range) or Produce a ~1.75-inch Hole Going Into A Man, and Leave a ~8-inch Hole Coming Out the Back of a Man at 1,000-meters. And that’s JUST Using “Ball” Ammo, Think What It Would Do Using “AP, Armorer Piercing” Ammo. No “Very Conducive” in an Urban Area. The Most Likely Reason on Limiting It’s Range…

    8. @ Mikial.

      I’m Aware to the Fact this NOT going to be Distributed to the General Public. But Other Websites that I’ve been on. Some People Are Extremely Confident That They Are, INCLUDING “Smart Bullets” and Man-Portable Rail-Guns…

    9. @Secundius:

      Let me bring this discussion back to simplicity.

      The ammo in this article sucks, the article says “funding for the project has ceased”, and in urban areas why don’t they just load Federal HST JHP’s in their AR-15’s?

    10. @ ss1.

      EXACTLY, What the Point of Having A DISCUSSION on a “DEAD SUBJECT”? IT “Solves” Nothing and IT “Resolves”, Nothing…

  6. Thank God all small arms come with laser range finders and there are little dials on each bullet so you can program them for the right amount of distance rather tyan carry multiple mags with different roundsbfor diffetent distances. It also helps that the enemy never moves and always stays in one spot. Ya right. What a waste if tax dollars.

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