Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


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  • KBCraig

    Yeah. Not impressed with the concept.

  • Obsidian

    I think the shrapnel pattern’s fine, you can actually still see a lot of it impacting the target (it was apparent to me anyway) even if it detonated like a yard or two away, so I think that the system’s pretty good

  • James.Denholm

    I imagine the target’s ears wouldn’t come off unscathed, though. Where fragmentation fails, flash-bang prevails!

  • bbmg

    In spite of appearances, the forward velocity is probably irrelevant. The round leaves the barrel at less than 700 feet per second (presumably much less when it reaches the target), while the velocity of fragments from the grenade would be in the region of 5,000-10,000 feet per second, so there will only be a slight difference in damage between targets forward and to the rear of the detonation point.

  • Ross

    I’ve watched high-speed videos of XM-25 rounds exploding, and yes, it looks like most of the shrapnel is forward of the detonation point, though the target would presumably still be hit with the shockwave.

    This brings up a related, but more broad question, if any reader knows the answer. If a super-sonic projectile detonates, is the speed of the detonation’s shockwave relative to the speed of the projectile at the point it detonates? In other words, does the shockwave ahead of the projectile’s point of detonation travel at the speed of the projectile plus the speed of the shockwave, and the speed of the shockwave behind the projectile’s point of detonation travel at the speed of the projectile minus the speed of the shockwave? I’m curious about this, because if the shockwave’s speed is relative to the projectile’s speed, then a target behind the point of detonation could possibly escape unscathed, assuming the shockwave’s speed minus the projectile’s speed is relatively small.

    Or maybe I’ve had too much coffee — haha!

  • Lance

    I saw another video too. The XM-25 looks like it kicks like a mule to the shooter.

  • Meltron

    True the shrapnel may not injure them physically with metal, but an explosion near the head will certainly blow out their eardrums and cause more disorientation than a flashbang potentially.

  • jdun1911

    Not impress. You have a grenade going off point blank range in front of the manikin and it didn’t blew it head right off.

    Is the shrapnel made out of birdshots because it look like it at my end.

    Unlike flash bang you won’t have people going in for the kill.

  • charles222

    Yeah, concussion is just as effective as actual shrapnel in certain ways; certainly we’ve seen enough soldiers with TBIs from IED blast that that isn’t really a debate anymore.

    And Lance-it’s a weapon with a third of the mass of a Barrett firing projectiles twice as heavy as a .50 cal round…of course it’s going to kick like a mule. :p

  • Thomas

    The dispersion pattern from the ADR is in a forward cone covering a little less than 180 degrees. For it to be of optimal effectiveness, the round has to detonate so the target is within the cone, yet without any intervening barriers. The problem with these weapons, as used in combat, is that their effectiveness is largely unknown. To date, no casualties have been recovered during the application of the weapons in theater. We simply don’t know how effective they are or what kind of counter measures may be available or developed to render them ineffective.

  • Ryan

    Anyone know what the soldier in the background is holding at 00:55 It seems to have some large attachment on top of it as well.

  • http://votefordavid.blogspot.com Vote For David

    Are we seriously comparing this thing to a flash/bang launcher and not also howling outrage about its lack of utility?

    If it doesn’t blast everything to smithereens on a near-miss, it’s a fail. Flash/bang from far enough away to regain orientation and return fire seems . . . not so useful.

  • Rohan

    @Ross.

    Newtonian physics still hold.

    Most HE round travel up 1000-1200 m/s at the muzzle.

    When a shockwave is created by high explosives such as TNT (which has a detonation velocity of 6,900 m/s), it will always travel at high, supersonic velocity from its point of origin.

    Fragments travel about 1500m/s.

    1500m/s less 1000m/s-1200m/s => 300-500m/s fragments backwards.
    That will still wreak your day.

    As for XM-25 the fuse is in the tail.

  • Jon Mac

    That’ll be the M320 (M203 replacement) with stock fitted;

    http://en.wikipedia.org/wiki/M320_grenade_launcher

  • subase

    Maybe scaring the crap out of and not killing the taliban and other suicidal fanatics with this weapon isn’t such a bad idea.

  • Hauser

    @Ryan, the thing in the background at 0:55 is a stand alone M320 40mm grenade launcher.

  • bbmg

    If you look at the explosions at around 37 seconds into the videos, you can clearly see fragments going through the “window” frame, even though the round detonates well past it. All representations I’ve seen of the 25mm grenade (second in this lineup: http://www.quarry.nildram.co.uk/grenades.jpg ) indicate it has both front and rear warheads, so there is every reason to believe the fragmentation effect is uniform both forwards and backwards of the round detonation.

    That the mannequin’s head is not blown off is irrelevant, if it’s been peppered with hypersonic fragments, it’s still taken out. Also, a wooden mannequin is not going to display the same reaction to high velocity fragments as a living target would.

    Even if the fragments are the size of birdshot, they are travelling faster than they would out of any shotgun. A fragment from an M61 grenade has an intial velocity in the region of 6,000 feet per second, at least three times faster (and therefore with 9 times the kinetic energy) than typical birdshot fired from a shotgun.

    In short, without the chance to examine the damage first hand, it’s unfair to judge this weapon system as ineffective.

  • Riceball

    I think some of the readers here have too seen a few too many Hollywood movies and believe that grenades actually detonate with huge fireballs. A grenade doesn’t kill by means of sheer explosive force and blow things to smithereens, it’s not a bomb, instead it’s meant to kill through shrapnel. In the case of the XM-25 it’s meant to be a precision fire weapon that allows to send a 25mm grenade to a precise point, like at an insurgent taking cover behind a second story window and sending that grenade through the window to detonate right in front of his face. Will it blow his head off, no, but a face full of shrapnel from a 25mm grenade will sure ruin his day and being relatively small, the blast radius isn’t too large so that if there are any civilians in the building with the insurgent there’s a goo chance that they won’t catch much, if any, of the shrapnel unlike a conventional grenade.

  • Mountainbear

    Give me a frag grenade, thank you.

    If I strike an enemy position, I want to do as much damage to everything in it as possible.

  • Mountainbear

    Another thing that came to my mind. I’m on patrol in a town. We’re being attacked from a prepared position. What am I going to do?

    Dig and, get whoever is lugging this thing around and have them open up? Allowing the enemy, who certainly knows the area, to eventually get to me? Or will I flank first and get a normal frag grenade into their position?

    I’m for not losing initiative.

    Also, that thing means that one of my soldiers would not carry an assault rifle. If he would, he’d be bogged down by too much weight. Plus, it doesn’t strike me as a weapon that can quickly react to changing conditions like, let’s say, a SAW.

    Yeah, I’m not really convinced of it. For some peacekeeping stuff, maybe, but for real combat… I don’t know.

  • Mountainbear

    Riceball, that’s the issue I have with it. It’s not a weapon for war. In the combat situation I don’t think I’d give a damn about any civilians inside a prepared insurgent position. For all I know they could be sympathizers or part of the enemies.

    WW2 wasn’t won like that. It was won by bring out the ugly stick.

  • TJ

    Nice that they’re still teaching follow-through. Or is it really that high tech that the targeting system takes care of everything?

  • Some Guy

    I think most of you play a little bit too much call of duty. Most grenades do not make gigantic explosions, yet they still kill just fine.

    http://www.youtube.com/watch?v=psg-jiL86mg

    40mm grenade!

  • jdun1911

    Riceball,

    It’s about penetration. When you have a grenade going off in front of the face I expect serious damage. That not even the case in the video. If it can’t kill what the use of carrying it? There are reasons why 40mm are prefer.

    Again what will the Platoon/Squad leader replace in order to fit this weapon in the group? Rifleman? Grenadier? Automatic Rifleman? That’s a lot of firepower a Platoon or Squad is giving up for a weapon that does too little.

  • Rohan

    @BBMG

    The second cut away of Tony’s is the HV 25mm. The first round is the shorter XM-25 25mm round. It appears to have the fuse at the base and only one bursting end.

    Please my old post on a firearms blog about XM-25. Note the grenade is small about 120 gram that has to include fuse, explosive and metal shell. This is half the 40mm grenade.

    Blast has very limited range (a meter or two) with such a small charge. Fragments will travel at 1500m/s, but size, weight and number affect their range. A human has a surface area of about 1m2. Only half can be hit by metal, you need one fragment per m2 for a hit, more for a kill.

    Inverse square law comes into play. At 2m a sphere has a surface of is 50m2, at 4m 200m2, at 6m 452m2, at 8m 800m2 and at 10 1256m2.

    Unless you can produce 452 effective fragments for a sphere of 6m (226 for half sphere) you will not hit you target.

  • Bill

    You guys are missing the big picture. This weapon allows for the defeat of an enemy BEHIND cover from 500 meters away. You must be some sort of supermen to throw an m67 that far.
    This could be a total game changer. Go ahead and manuever your fire team while under direct fire, then have someone break cover to move up to throwing range of the target, then throw and hope they don’t miss. God help them if they are throwing to a second or third story window. If they do miss that grenade is coming right back down on em.
    Me, I’m going to nod to the guy in my squad who is humping this to take his shot, then we are gonna chuckle (maybe even giggle; infantry units can be strange) when the boom goes off.
    Hell, even in a movement to contact scenario in open terrain this thing has crazy potential. Most skirmish lines don’t have much depth so you could laze a tree next to one guy and then fire off a spread along the whole line. I can’t wait to get my hands on this thing.

  • Brad

    “What is interesting is watching the shrapnel pattern. If the grenade was detonated two, or maybe even one, yards behind the target, the target could escape unscathed or with very minimum damage.”

    Watch the final frames of the video clip and you can see the fragments kicking up dust from the ground. Judging by the scale of the target dummy the fragmentation pattern is considerably larger than one or two meters in depth. To my eye it looks to be at least 3 meters in depth.

    Is 25mm too small a warhead? How small is too small a warhead? Judging by the standards of conventional fragmentation hand grenades, the 40mm grenades fired from M203 grenade launchers are too small for effectiveness in combat too.

    Off topic, but I’ve been wondering — what is the minimum range a typical 40mm grenade launcher can be used for indirect fire?

  • Bill

    I think your math is wrong man. A sphere with a surface area of 452 square meters would have a diameter of 12 meters not 6.

  • Rohan

    @ Bill

    Mr crazy Taliban will shoot your xm-25 guy first and have a chuckle, shoot a RPG into the tree above you and mince your fireteam and have a giggle when he cut your nuts off.

  • jdun1911

    Brad,

    Have you seen the pattern for a hand grenades? It’s very impressive. It does what it suppose to do, kill the enemies.

    No one is complaining about the lethality of the 40mm.

    Both does it job well in regards to its scope.

    Bill,

    At 500m you call in CAS, film and put it on youtube.

  • Bill

    Depends on if it’s urban or not. At 500m of open terrain I indeed woulld call for CAS or indirect.

  • Rohan

    @ Bill

    Sphere with radius of 6m (ie from burst point), not sphere of diameter of 6m meters.

    Grenades are quoted as burst RADIUS.

    “A sphere with a surface area of 452 square meters would have a diameter of 12 meters not 6″.

    The surface area of a sphere is given by the following formula

    Area = 4 x pi x radius square.

    Area = 4 x 3.1415 x 6 x 6

    Area = 452m2

    I think my math is right man. Your assumption is wrong.

    Just for your information (and to show I am a morbid soul) I have the real world results of a grenade explosion in Australia.

    http://www.mja.com.au/public/issues/may19/nocera/nocera.html

    A F1 grenade exploded during production. Remember it has 4000 2.5mm steel balls, a 6 meter lethal radius and 15 meter injury radius. Only 4 of the 7 present were injured. All survived, just.

    http://www.mja.com.au/public/issues/may19/nocera/nocbox.html

    At 6m radius a 375g F1 grenade has about 9.5 fragments per meter. A XM-25 grenade shell is only about 100-120g. Even if you assume that that shell breaks perfectly into 2.5mm bits thats only 1000 fragments (which it won’t because it has to have walls thick enough to survive firing), the lethal radius will only be 3m (radius).

    The xm-25 is great in theory but fragmentation has lower lethality than bullets. During WW2 2/3 of wounds were due to fragments, but 2/3 of deaths were due to small arms. It depends on your aim (no pun intended). Unless you hit with a meter or two of the target the effects will be disappointing.

    http://history.amedd.army.mil/booksdocs/wwii/woundblstcs/default.htm

  • Obsidian

    Brad

    Maybe 30mm would be a good compromise between 25mm and 40mm, it’s not so small that there isn’t enough boom, but it’s not so big that it’s too heavy, I’m thinking this should be fine.

    Mountainbear

    A back up weapon could be used with this weapon for the guy who’s humping this thing (something like a La France M16K or a Magpul PDR) coupled with a few extra magazines and his sidearm and knife, I think he should be fine. The fears that the XM25 is too heavy to prevent proper self-defence would be unfounded as long as the ammunition for it is limited to 1 or 2 extra magazines (I think)

  • bbmg

    “A F1 grenade exploded during production. Remember it has 4000 2.5mm steel balls, a 6 meter lethal radius and 15 meter injury radius. Only 4 of the 7 present were injured. All survived, just.”

    … thanks to prompt evacuation to adequate medical treatment facilities which no doubt bear no resemblance to those available to the intended targets of the XM25. I don’t think this is a fair representation of battlefield reality.

    “Unless you hit with a meter or two of the target the effects will be disappointing.”

    Isn’t this the point of the XM25’s intricate targeting system? In order to achieve a portable weapon that could fire at high enough velocity for a reasonable flat trajectory, the size of the round was always going to be a compromise, and I agree that fragment size and number is no doubt limited. However the trend these days is towards weapon systems that are accurate enough not to need a warhead that can level the whole neighbourhood.

    A 40mm grenade would no doubt make a bigger bang and cause more casualties over a wider radius, but it’s unlikely that its rainbow-like trajectory would allow it to make use of precision fusing, as a lower velocity larger projectile it would be more prone to environmental factors which the targeting system would not necessarily compensate for.

  • bbmg

    One avenue that might be worth exploring is a 40mm sabot round. The idea is that you would have a projectile similar in weight and explosive/fragment content to current 40mm grenades, however shaped like an APFSDS anti-tank projectile, ie a slender aerodynamic dart of say 25mm diameter.

    The muzzle velocity would be about the same of current rounds, but the reduced cross-sectional area, better aerodynamic properties and increased sectional density would result in significantly greater velocity retention, meaning less time to reach the target and a flatter trajectory, increasing accuracy to the extent that use of the XM25s optics and electronics could be feasible.

    Current 40mm rounds have terrible aerodynamics and there is much room for improvement in this area, which can be achieved for the same projectile weight and recoil.

  • Rohan

    @BBMG

    A far, far simpler solution is a 30mm UBGL with a laser ranger and fuse setter (STK and IMI already have 40mm variants).

    30mm long cylinder shell (better frag’ pattern),
    with air-burst base fuse (of the 25mm shell)
    same weight as 40mm (bigger bang than 25mm),
    but better BC than 40mm (but not as good as 25mm),
    gives longer range with the same kick (LV 500m, MV 700m)
    with a midway trajectory (better for air-burst, shooting fragments downwards & forwards into target).

    Put it in a lightweight composite UGL and add it to a 6.5mm rifle.

    A simple cheap OIWS (Objective Individual Weapons System).

  • Rohan

    ESTIMATED LETHALITY OF WEAPONS IN KOREA

    Lethality (% Killed out of those wounded)

    Wounding Weapon Killed in Action Killed and Died of Wounds
    Small arms 0.23 0.26
    Explosive projectile 0.20 0.22
    Shells, rockets, and bombs 0.17 0.34
    Grenades 0.03 0.04
    Land mines 0.22 0.25
    Other fragmentation munitions 0.50 0.54

    ESTIMATED LETHALITY OF WEAPONS USED AGAINST THE US ARMY DURING WORLD WAR 2

    Lethality (% Killed out of those wounded)

    Wounding Weapon Killed Killed and Died
    Small arms 0.34 0.38
    Explosive projectile shells 0.22 0.26
    Rockets and bombs 0.22 0.26
    Grenades 0.05 0.08
    Mines 0.18 0.22

    http://www.bordeninstitute.army.mil/published_volumes/conventional_warfare/ch02.pdf