For a change I thought I would feature an interesting military munition for todays POTD. A reader sent us this photo asking if we could identify it and if it was a real cartridge. It is indeed real, but it is not a firearm cartridge. This round is a 30mm AHEAD Air Burst Munition (ABM) manufactured by Rheinmetall Air Defence AG.

It is designed to be fired from integrated/automated air defense systems. Radar first identifies and tracks the heading and velocity of an incoming target. This targeting data is fed into an anti-air  auto-cannon’s targeting computer. The cannon then programs the AHEAD projectile’s fuse electronically just prior to firing. The time from first identifying a target to firing the first round is less than 5 seconds (in an ideal situation).

The fuse it set so that it explodes in the air just ahead of the target.  Those cylinders you see in the photo are actually stacks of tungsten discs. Each projectile contains 150 discs, each weighing 51 grain. The total weight is equivalent to 11 .50 BMG projectiles. The direction of the discs is controlled and they are stabilized in flight by their shape.  If all goes well the target will fly at full speed through multiple clouds of fast moving tungsten discs, ripping it to shreds.

But, like all air defense, the actual munitions are only as good as the radar systems. You cannot hit what you cannot see (or track reliability).



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  • jolly

    Cool.

  • The Librarian

    The AHEAD system is actually based on the 35mm Oerlikon automatic cannon.

    For more interesting Rheinmetall ammunition, look into FAP and PELE.

    • Mario AK

      My thought exactly, I thought it was proprietary…

      • Giolli Joker

        Same here, I didn’t know there was a 30mm version.
        http://www.rheinmetall-defence.com/en/rheinmetall_defence/systems_and_products/weapons_and_ammunition/direct_fire/medium_calibre/index.php
        Defining the sub-projectiles as discs is a bit misleading, they’re actually cylinders with diameter shorter than length.
        (If you’re willing to follow The Librarian’s advice, don’t google just FAP…)

        • CrankyFool

          I’m not sure there’s a contradiction between “disc” and cylinder, though that’s mostly because there’s no formal definition of “disc,” but there is of a cylinder: A geometric shape with straight parallel sides and a circular or oval cross-section. By that definition, I suspect anything we think of as “disc” is a cylinder. I suspect your error may be in thinking that the formal definition of a cylinder is that its length is greater than its diameter, but that’s not the case.

          • Giolli Joker

            Well, the first definition of disc that I can find with Google is:
            “1. a flat, thin circular object.”

            I don’t know if there’s a “formal definition” for disc or cylinder, any 3D disc is surely a cylinder, my point is that, at least by general knowledge, a disc IS a cylinder having a diameter greater than its length (same thing you said but read from the opposite side), hence “a flat, thin circular object”.

            If I read disc, I think coins or DVD, or considering we’re talking about projectiles, Frisbee or flying saucer… something that would have a flying pattern completely different from the sub-projectiles we have here, designed to hit with their circular face.

    • Rheinmetall bought a majority stake in Oerlikon Contraves AG back in 1999, and bought out the remaining stake holders in 2003. In 2009, Oerlikon was renamed Rheinmetall Air Defence AG.

  • Dr Sick

    I hope fps russia will test it…

  • lurker

    Is it fused before firing, or after firing? Perhaps the fuses are set by induction coils at the muzzle.

    • MrDakka
      • S O

        No, at the muzzle, with electromagnetic induction.

        “a programmable fuse, which is supplied with data from the fire control
        computer via an electric fuse programming coil as it departs the barrel.
        After measuring the current velocity of the round, the electronics
        calculate the optimum detonation time, inductively programming each
        round as it passes through the muzzle.”

        (your link)

        The muzzle velocity isn’t measured by radar as with most big guns, but most likely by measuring the spin (twist rate of the barrel is known, after all).

  • guest

    I wonder what the efficiency of this is versus conventional HE/HEI ammo. This looks like purely kinetic weapon, and I am guessing tungsten is only used because of high density and not for some AP function or whatever. So the further away the target is, even in the engagement envelope, the less effective the terminal effects must me. Not so with any round having the HE component.

    • phuzz

      These rounds are designed to take out incoming missiles, so I suspect they would still do their job even if the discs were effectively stationary in the air. It would be like flying through metal hail for the missile.

    • Giolli Joker

      You have a bullet that leaves the muzzle of the cannon at a velocity in the 900m/s range, when it’s close enough to the target the charge behind the sub-projectiles sets off, launching them forward at a final velocity probably north of 1500m/s, in a conical/spiral pattern due to the rotation given by the rifling on the original bullet.
      Think of shooting a full buckshot shell that sets off at optimal distance to the target.
      I can hardly think of anything more effective out of a cannon, for the intended purpose (mostly defense from missiles).
      It would probably wreak havoc as well on anything not seriously armored.

      • geust

        The tiny fuse/charge behind the “discs” is probably just powerful enough to open up the projectile and let loose the “discs”.
        1500m/s is a lot of horse doo doo because that is velocity of fragments from shells packed with LOTS of HE, like 40mm timed Bofors shells with pre-fragmented warheads, so you are pulling that number out of thin air.

        As far as the rest of your arguments – AA has historically used fairly conventional HE shells. Velocities of 1500m/s and beyond are attainable, along with terminal effects like delayed fuses to detonate inside target for better effect rather than instant action. Plus a bonus for any AA munitions is if they are also incendiary – for example of fragements would be zirconium or the like. Having “every little bit help” in the case of AA makes the case for this already aging tech.
        IMHO a much better result would be attained for simply using regular HEI shells and timing them individually. Any decent AA gun always has a high fire rate, and if 1 out of 1000 shells makes a direct hit, it will always do more damage than the fragments of the other 999 even if they do go off very close.

        • Giolli Joker

          The source I had read was on paper so I can’t quote it, however:

          “AHEAD gives the 35DPG its anti-missile capability. The crux of the
          AHEAD system is timing the flight of a round fired towards the point
          of impact in such a way that at a distance of somewhere between 10
          and 40 meters ahead of the target, 152 heavy tungsten metal
          sub-projectiles are released from the round.1
          This cloud of sub-projectiles then flies towards the approaching
          target and on impact tiny spin-stabilized tungsten cylinders, each
          weighing 3.3 grams, penetrate into the target body – even at low
          angles of impact. Due to their high kinetic energy (the relative
          velocity is about 1,200 m/s), they can be expected to cause massive
          damage to the target’s functional system components. The precisely
          timed ejection of the sub-projectiles is only ensured if all
          critical functions are perfectly coordinated. “To achieve this,
          absolutely accurate target tracking is required in order to
          calculate the projectile flight time from the gun muzzle to the
          optimal point of sub-projectile ejection. The time fuze of each
          AHEAD projectile is programmed at the muzzle velocity measuring
          base, depending on its individual muzzle velocity,” Rheinmetall
          argues.”
          From here: http://www.defenceweb.co.za/index.php?option=com_content&view=article&id=6656:fact-file-denel-35mm-dual-purpose-gun&catid=79:fact-files&Itemid=159

          1200m/s, not slow I’d say.

          This ammunition is regarded as one of, if not THE, most effective in it’s role.
          But if your opinion is more relevant for you… good for you, changes are you’re not really needing to defend yourself from incoming missiles.

      • S O

        “when it’s close enough to the target the charge behind the
        sub-projectiles sets off, launching them forward at a final velocity
        probably north of 1500m/s”

        No, there’s no charge to add velocity and it surely wouldn’t add that much energy anyway.
        There’s merely a charge to open the cargo round to release the pellets.

        The impact velocity on a standing target at 1 km distance is likely 650-800 m/s only.

    • Tom – UK

      Don’t forget the plane is not stationary, lets say the plane is flying at 700mph (312ms) and the cylinders are moving at 1500ms (as suggested in another comment). The mere fact that the plane is moving adds 20% energy to the impact when the cylindey hits.

      Another way to look at it is that it would be the same as a stationary plane being hit by the cylinders at 4050mph/1812ms. I certainly would not like to be the pilot.

      • guest

        1500 is a number pulled out of that commenter’s ass, and you are augmenting it by claiming the velocity would increase further as if the plane was diving STRAIGHT AT the shells.

        I am guessing the target plane in this case would be a jet-powered dive bomber, better yet a JU-87.

        • Tom – UK

          Even assuming the 1500ms is false the fact still remains that no matter what angle of impact it is still hitting a plane that is under a great deal of stress and is made up of thin sheet metal.

          • guest

            Oh no, a great deal of stress on the skin! You do realise in Korea Mig-15’s made it back with as many as 160 (!!!) .50 APIT/IT hits?

          • Chrome Dragon

            Remember, this is an antimissile round. There’s not a lot of cross section for .50 to hit, but neither is there very much between this piece of nasty and, say, the critical guidance optics. On some missiles, any head-on engagement could be expected to destroy either the seeker, or the window protecting it from a blast of mach 1+ air.

    • jason

      Modern jet engines do not react well to non-gaseous intake materials, even titanium bladed military engines. Think about dropping gravel into your blender… now imagine your blender is spinning at ~12,000 rpm. 🙂

  • Will

    Think high speed high, high dollar, skeet.

  • S O

    It’s for the Puma IFv and actually a very poor choice in my opinion.

    Up to 1000 m they could have done the same with 7.62 mm coax, but they chose a marginally smaller 5.56 mm coax instead.

    Beyond 1000 m Ahead has some advantages at least against air targets, but the maximum gun elevation is only ordinary.

    They are now lacking a proper, versatile HE cartridge because they fell for this electronically timed expensive kinda shrapnel/kinda cannister round.

  • Secundius

    Nice, where can I get one and how much?