Larry Vickers And Grenade Launchers (HEDP Footage)

Larry Vickers’ TacTV YouTube channel has released a series of videos showcasing 40mm underbarrel grenade launchers, including uncommon footage of firing actual high explosive dual-purpose (HEDP) grenades. The videos are embedded below:

The underbarrel grenade launcher is one of the great innovations of the post-WWII world. While less elegant than rifle grenades, underbarrel grenade launchers can be mounted to anything that will physically accept them, and since they operate independently from the rifle, allow a lot more freedom both in the design of the rifle and the cartridges it fires.

Muzzle-fired rifle grenades are another similar concept that was developed earlier and saw use in the Second World War, however they suffer from some substantial limitations that the underbarrel launcher does not. First, they are highly dependent on the ammunition characteristics, both charge and projectile, of the rifle being used as a launcher. Whereas an M203 has exactly the same trajectory when mounted to anything from an MP5 to a G3, rifle grenades produce different trajectories depending on the rifle they are fired from.

Likewise, rifle grenades suffer from a dilemma regarding the projectiles used by the host rifles. The simplest solution is to use a blank projectile, but this prevents the rifle from being used as a grenade launcher, and then immediately again as a rifle (firing grenade, then “cleaning up” with small arms fire). “Soft” projectiles (e.g., M193, M80) can be used in bullet-trap and bullet-through style grenades, but armor-piercing projectiles are only compatible with the bullet-through type. Shaped-charge warheads, a very useful type that offers both an explosive radius, as well as excellent armor penetration capability even against well-armored AFVs, do not synergize well with the bullet-through configuration, meaning that essentially one has to choose between armor-piercing rifle ammunition and shaped-charge grenades.

Finally, rifle grenades negatively affect the life of the host rifle, usually cycling the action very violently while stressing the frame of the rifle much more severely than normal firing would. As a result, rifles optimized to fire muzzle-mounted grenades are typically much, much heavier and more robust than their counterparts.

The underbarrel grenade launcher circumvents all these disadvantages while providing additional accuracy of fire, with the tradeoffs of extra weight on the rifle (from the launcher itself) and smaller, less capable grenades. Many rifles, such as the M4, are compatible with both rifle grenades and underbarrel launchers.

Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at


  • BattleshipGrey

    Thanks for posting Larry’s vids. I’m subscribed to his channel, but I don’t have time to watch everything I’m subscribed to. You definitely post the ones that are note worthy and informative to us “little people” that can’t have access to fun toys like this.

  • MPWS

    As I imagine, grenade launchers are not common subject for majority of civilian shooters (and so much less hunters:-))) but still, very good general knowledge subject.
    Thanks for bringing this up and keep going. You may want to touch on pre-programmed 40mm versions such as Singapore’s and Israeli products. They are probably on vanguard of current developments.

    • LCON

      The US army and Marines are both looking at that tech for possible retrofit into M203, M32 and M320

  • Micki

    I believe the Italians had a side-mounted grenade launcher for the Mannlicher Carcano carbine, as far back as 1928. Unfortunately, to use it you had to remove the bolt from your rifle and put it in the GL. It was known as the “Tromboncino” apparently, and didn’t work too well. One for Forgotten Weapons, I think!

    • Rifle grenades date back to the First World War, so they were still earlier. I hadn’t heard of the tromboncino, though, that is fascinating, thank you!

      • Micki

        And as for stand-alone GLs, the Germans had their Leucht/Sturm/Kampfpistole series in WW2, of course, firing all kinds of explosive munitions and flares. Nobody thought to clamp one under a Sturmgewehr though, as far as I’m aware.

  • MR

    Notice the position of his hands in the first two images. Grog’s website has a good explaination as to why you want to keep your hands away from the barrel/tube of the launcher, especially if using reloaded/aftermarket ammo. (Catastrophic failures and do-it-yourself hand amputations)

    • Yeah the civilian buyers of 37mm and 40mm launchers do not get told how to handle the launchers properly. So you get the occasional hand removal job occuring due to a faulty 37 or 40mm round. Even a 24 mm round that underwent a failure could potentially remove a hand.

  • Martin M

    I need a belly like that so I can rest my rifle on it like Larry.

    All kidding aside, that’s some great shooting by Larry.

    • Nicks87

      He earned that belly, believe it or not it’s actually quite tactical.

      • KestrelBike

        His “Why I’m Fat” video is awesome. Man can be as damned fat as he wants, with what he’s accomplished in life and for his dedicated service. I just hope he stays fit enough to live long & keep sharing his knowledge.

        Now for the grenades, wow they really aren’t that damaging. Interesting to learn about their small blast radius.

    • nadnerbus

      Someone in a youtube comment made a good point. When these guys are still in, they are either training or deploying almost all the time. They probably eat 4 to 6 thousand calories a day and need more, for the activity they do. When they get out, it is a pretty big swing from constant physical exertion to relative sedentary lifestyle. But the appetite stays the same. Add in physically debilitating injuries that make exercise hard or impossible, it’s easy to see how a guy could pack on some pounds.

      He still looks like he could break me in half without too much trouble.

      • Nicks87

        Yep thats no joke I run into a lot of guys at the Veterans Hospital that are in the same boat. Sometimes it’s a tough transition back to civilian life, in more ways than one.

  • Blake

    Something about the phrase “bullet-trap rifle grenade” sends cold shivers up my spine…

    • nadnerbus

      What could go wrong with firing a bullet into a chunk of high explosives?

      • KW6

        Actually, you’re firing a bullet into several chunks of metal, which deform to trap the bullet. The transfer of energy yanks the grenade off the muzzle. The trap and bullet are safely away from the explosive charge.

        If you want something to worry about, consider that a gas-launched grenade is essentially a the opposite of a normal round — you’re launching the “cartridge case” off the thing that’s inside it. And you’re doing it with a blank, which creates a MASSIVE amount of hot, burning gas, far more than the live round which makes the BT go. The slightest flaw in the gas trap can let some of that stuff go places that you don’t want it, or can push the thing off course, or even spin the grenade far enough out of line that the detonator doesn’t trip on impact.

        The big advantage of the BT is that, once the grenade is gone, you have a fully-functioning rifle — no changing gas plug settings, the empty case is ejected normally, you’re just automatically in business.

  • wildbillb

    he called me ‘baby’. twice.

  • KW6

    The FN FAL (and clones), as shipped to most military users, can easily be converted to fire grenades — all it takes is to replace the gas cutoff plug with one that has a grenade sight attached. When not in use, the sight curves over the top of the forearm — flip the sight up, rotate the gas plug to the “S” position (gas is cutoff, the rifle must be cycled manually), and the sight then can be used. The rifle can be used with normal ammunition even in this configuration, and a variety of grenade types can be used. These simply slide over the Multi-Purpose Device (the “fat” muzzle brake, not the blade-type found on the L1A1).

    Since most grenades come packaged with the appropriate round for launching, there isn’t much of a logistics problem.

    In Rhodesia, during the war against the terrorists who finally won, it was common for one or more troopies in a patrol to be loaded with anti-personnel grenades. When ambushed, he would launch the grenade, and the rest of the magazine were standard rounds. He could cycle the action by hand until he had a moment to swivel the gas plug back to “A” for action-cycling.

  • valorius

    I carried an M203 for some time in my platoon. Got to fire a lot of TP rounds, but never a live HE round. Pretty easy to shoot accurately with the leaf sight.

    You can actually lay down a mindboggling amount of fire with an M203 if you have a loader.