M79: The Iconic “Bloop Tube” 40mm Grenade Launcher

Combat experience with the bazooka rocket launcher in World War Two and its larger versions in the Korean War convinced the US military that a better weapon was needed to give front-line troops a direct-fire way to attach enemy strong points. The bazooka was bulky, not particularly accurate, and created a lot of backlist signature when fired. This led to a multi-part development effort involving design of a small grenade body, reliable but cheap fusing system, and a cartridge design that could launch it.

The result was the 40x46mm grenade. It uses a “high-low” system (originally developed by Rheinmetall during World War Two) in which a powder charge is fired in a small compartment within the cartridge case. The initial pressure in this compartment is some 35,000 psi, which is plenty high to ensure complete and repeatable powder burn. At peak pressure, the internal compartment ruptures, allowing the propellant gasses to expand into the full case volume, which lowers the pressure to about 3,000 psi. This lower pressure is safe to use with an aluminum barrel, and propels the grenade at about 250 fps, giving it a range of about 400 yards without generating excessive recoil.

The M79 proved to be very accurate and reliable. It’s downside was the need for a grenadier to carry a backup sidearm, as the M79 could not be used at close range. Almost as soon as it was introduced, work began on developing a launcher which could be attached to the M16 service rifle. This would first be the XM-148, and then ultimately the M203 that would replace the M79 in service. M79 launchers can still be found all over the world, however, as they are robust and reliable.

Book review of Roy Rayle’s “Random Shots” (which includes M79 development).

66 Comments

  1. Hi Ian, I agree this was a very simple design. The most important tech behind this is the round and the rifling. This would be a good subject for M79 2.0
    Best!

  2. My brother carried a 79 and 1911 during his tour in Vietnam with the 1st infantry. He was issued a couple of experimental buckshot rounds but watched a skinny NVA soldier jump up and run away after he’d shot the guy at about 20 yards. So he went back to the 1911 for up close and personal work. He said that a good 79 gunner could get more range by kneeling and bracing the weapon against the ground like a light mortar. The gunner would operate the breech and trigger and an assistant would load the rounds. He said that he could walk rounds into a target out beyond the 350 yard setting on the sight.

    • Thanks for the useful and interesting firsthand info. Using it like that makes it sound a lot like the Japanese Type 89 “knee mortar” from WWII.

  3. The bazooka angle is interesting, and I hadn’t heard about that before.

    I would have liked to hear about rifle grenades and why they weren’t considered adequate. Obviously the M203 combination has its advantages, but before its development a rifle with the option of a bullet-trap grenade would seem preferable to an M-79 and a pistol.

    • Mike, my understanding is that these were some of the problems with rifle grenades:

      1. Because they had no barrel, they needed their own spin stabilization apparatus, which is why they are long and have fins on them. Hard to carry very many due to weight and size.
      2. Their propelling force is the rifle round. So, they either have to have a bullet trap (as you mentioned and which of course adds weight since it needs to be substantial) OR there needs to be special rifle ammunition with wooden bullets or no bullet to launch the grenade (this system was common also). Of course, in the latter system, if you mistakenly fire a normal round into the rifle grenade on your muzzle…
      3. With a grenade mounted on the muzzle, you have invalidated the rifle for its primary purpose. In WWII, I’ve read that some US infantry squads had an M1903 for grenade launching. OK then, why not just give that guy a lighter weapon (M79) with lighter ammo since already wasn’t a regular rifleman?
      4. Separate sighting systems had to be added to the rifle for rifle grenades. I owned a French MAS 49 which had built in grenade launching sights…the sights were clumsy and awkward (small and on the side of the rifle, slow to adjust).

      Again, that’s my understanding and I stand to be corrected.

      • Palmetto95,
        I’m definitely not “correcting” you; I would not consider myself an advocate for rifle grenades both because I am far from an expert in that technology, and because I believe the M203 offers the best of both worlds. I’d just offer that it’s a matter of perspective – primarily of which role / requirement is primary. I’d contend that offensively grenade-launching is an episodic or occasional secondary requirement, and defensively there’s no contest at all. In that light I’d offer a few counterpoints to yours:

        1. Occasional use – how many does one need? Enough to justify one of every 4-5 troops no longer contributing rifle fire?
        2. Can’t deny the added mass, but I know they made it work – and doesn’t the added mass become frag when it detonates?
        3.
        A. With a [bullet trap] grenade mounted on the muzzle, you have invalidated the rifle for the moment it takes to yank or shoot the grenade off, after which it’s a mostly loaded conventional rifle.
        B. With an M-79, you’ve taken away my rifle completely and left me a weapon with no defensive utility plus the ability to switch to a weapon with far less defensive utility than a rifle.
        I’ll take A.
        4. An M-79 is the bulk and cost of grenade sights plus the bulk and cost of a grenade barrel, FCG, locking mechanism, and stock. At the usual ratio, the sights seem cheaper and easier.

        • Rifle grenades don’t always play well with things like flash hiders and bayonet lugs. So you have to have a rifle designed to mount the grenades. And the recoil can break stocks under sustained use. I’ve seen photographs of WWI British SMLEs with wire wrapped stocks for firing rifle grenades.
          As for defensive use of grenade launchers, there’s a difference between personal defense and military defense against an attacking force. An M79 (or M203) may not be much use defending yourself against someone 20 yards away, but it’d be useful in a small unit firefight.

          • Yes, there certainly is a difference between personal and military defense – the vastly larger chance of confronting violence when one actively seeks contact with the enemy. In the latter case, my overall statistical contribution to the mission is small comfort while carrying a single-shot weapon that doesn’t arm for 90ft.

        • Mike,

          I think the M203 indeed is the best answer. Most major service rifles today have some sort of under-barrel type launcher option so that issue seems settled. But, that answer came later.

          I think if the decision is made to have a grenadier at the squad level, and the choice is a rifle with muzzle-mounted grenades or an M79, then the latter is the better choice. The grenades are smaller so the grenadier can carry more, especially since he isn’t carrying a loadout of rifle ammo too. The launcher itself is more effective. Lastly, he is trained with the launcher and more effective at putting grenades on target.

          If, however, the decision is made not to have a grenadier at squad level, then I agree having some riflemen carry 1-2 muzzle-launched rifle grenades seems a workable solution. Before the era of the under-barrel grenade launcher, many major military rifles were configured for launching them. The French MAS-49 and MAS 49/56 come to mind, as well as the Yugoslavian M59/66. Rifle grenades were a major part of their small unit tactics.

          • Even in offensive operations, because the targets are more often than not in some sort of fortification that a rifle can’t shoot through. A dedicated, trained grenadier is lovely for breaking that cover so the riflemen get targets.

      • Palmetto – Until a grenade launcher was developed for the M1, the TOE for a US Army rifle squad included a grenadier with some model of M1903. The M1903 lingered in this role until surprisingly late in WW2. IIRC, I read about it being used eithr on Saipan Or Okinawa

        https://www.quartermastersection.com/american/infantry-weapons/209/M1GrenadeLauncher

        https://www.rockislandauction.com/detail/48/1828/springfield-armory-us-1903-rifle-3006

        https://military.wikia.org/wiki/M7_grenade_launcher

      • “(…)Their propelling force is the rifle round. So, they either have to have a bullet trap (as you mentioned and which of course adds weight since it needs to be substantial) OR there needs to be special rifle ammunition with wooden bullets or no bullet to launch the grenade (this system was common also). (…)”
        Not necessarily – take look at MODEL 100 https://www.lonesentry.com/articles/jp_rifle_grenade/index.html
        it launch grenades without trap AND using live round.

        • Daweo, that is a good link. I was familiar with those also, they are pretty basic and short range though:

          “6.5-mm M38 (1905) rifle (at 40 degrees elevation)—82 yards
          6.5-mm M38 (1905) carbine (at 30 degrees)—109 yards
          7.7-mm M99 (1939) rifle (at 40 degrees)—104 yards.”

          Also: “The Japanese warn against using the rifle for ordinary fire while the launcher is attached.” This was not elaborated on but seems to negate the value of being able to use normal ammunition.

  4. Most fun I had in basic/tech school was firing the M79. The instructors could drop a round every time into the top of a 55 gallon drum at 300+ yards. Hitting was almost effortless on the range where the ranges were known. I think that out of 55 guys in our class nearly everyone qualified with it. Can you imagine an M79 with a red dot and a laser rangefinder tied together? Press a button, the sight adjusts, pull the trigger. Next customer please.

    • I agree, and how about this; 51mm mortars with new tech. High accuracy indirect fire could radically change things; wee air burst shells at head height negating body armour etc. Replace the rifle, everyone fires at each other with advanced mini mortars. Actually thats probably the downfall of the infantry guy and the rise of the machines… So its possibly not a great idea, he he.

        • But. It will be more accurate. The sabot could be 51mm… A 20mm bomb at head height would smoke folk. The round would know, stuff… Yes stuff. It would know. Such as hiding behind a rock, it would know. Bang!! Got this interesting spider drone thing that drinks blood for electric, 51mm round well under 920g.

          • I accept that is somewhat scary quoth the Raven. On the plus side its more of a Simpsons Halloween special than a usual episode. Currently… Currently. Caw!! Ho, ho ho.

    • You basically described HK’s M320. The M203 replaced the M79, but introduced a restriction in the length of the rounds. The M320 is another break open design, & b/c of its weight, is rarely mounted to an M4, but is carried slung w/ the stock collapsed by the grenadier. So in 50 years we’ve gone back to the M79 w/ a folding stock & a laser rangefinder.

  5. Our battalion S-4 was a gun guy, and someplace in a warehouse on Ft. Bragg in 1993 he managed to find some gorgeous M-79s. I don’t know why he couldn’t get 203s, but I sure wasn’t going to complain. When it comes to grenade launching, it just doesn’t get much better than The Elephant Gun.

      • S is the staff series abbreviation used by the US military. S-1 is Personnel (HR, for civilians…) S-2 is Intelligence, S-3 is Operations, and S-4 is Supply/Logistics. There are other functions, but those are the basic four. If it’s an S-series element, that is brigade/battalion level, and once you get above that, it’s a G-series, which also implies that it supports a flag-rank general officer.

  6. Per several books I’ve read by SOG guys, they used to carry one of these as a backup gun, but they pistolized it. Cut off the stock behind the grip, and the barrel ahead of the hinge, put a ring on it and hang it from your web gear, where it waited for emergencies.

    Which, if you were running recon as a One Zero, could be pretty bad. I’m sure you didn’t notice the recoil if you had to fire a 40mm grenade from a single shot pistol if you had several dozen NVA chasing you to the LZ.

    (see John Stryker Meyer, John Plaster, etc)

  7. The origin of the M79 as far as I understand wasn’t in comparison to bazookas (the M72 LAW arose from that), but rather from the Japanese Type 89 grenade launcher aka “knee mortar.” During and after WWII, after action combat reviews with USMC and US Army personnel in the Pacific praised this weapon. One I read said, simply, “Why don’t we have a weapon like this?”.

    Some nations went heavy into rifle grenades as part of their infantry equipment, but there are weaknesses with them and the US went in the direction of a more or less improved Type 89 which was more portable and effective.

    The M79 scene from “Apocalypse Now” was pretty cool…

    • I found the quotes I was referring to:

      Lt. Col. Lewis M. “Chesty” Puller: “I consider it imperative that the Army and Marines be equipped with knee mortars and only carry one type grenade.”

      Army Sergeant C.W. Arrowood: “The Jap knee mortar gives us hell. They come in fast, thick, and accurate. Can’t we have one?”

    • “The M79 scene from “Apocalypse Now” was pretty cool…”(C)

      There was a real prototype for this scene.
      Only, it was in Normandy.
      And the M1 carbine was used.
      And the whole squad carried grenades for the shooter. Tying bags of grenades on lines to their feet for a drop.

      • Hi Stiven. I think you will find that the M79 scene from Apocalypse Now came from the fictional book ‘Despatches’ by Michael Herr. He was a Vietnam War correspondent and the book was a best seller in its day (1977). Herr also was a scriptwriter for Apocalypse Now so I’m pretty confident this was the origin of the scene.

      • Daweo, perhaps it was but that (T148E1) was also a post WWII weapon. I think the origin of the entire concept was the perceived success of the Japanese Type 89 during WWII.

  8. CHICKENHAWK, Robert Mason 1984(ISBN 10 14303571. Huey pilot memoir. Tells of an incident when a trooper jumping on board slammed his M-79 on the copter floor hard enough to cause a discharge. Two miracles occurred. First roof of the copter smashed the nose fuse before it reached arming range. Second the round flew THROUGH the whirling blades without touching them. Thank you Lord ! Thank you Jesus !

  9. A neighbor of mine carried the M79 in Vietnam, he told me they usually stripped the front sight off because it was always snagging on things, and and just aimed by feel, still got “good enough” field accuracy.

  10. Actually, Stokes’ mortar, and possibly earlier.
    Anyway, artillery boosters for charges () were known long before that.

    Although, perhaps, the Germans gave it a more complete look.

  11. The unit we replaced in Iraq in 2007 had a captured M-79. I think they still used it. It is possible that was an Iran/Iraq war bring back that they picked up from the enemy. It wound up in the 2nd Brigade, 10th Mountain Division HQ in Camp Striker Iraq.

    My late friend Ed had a platoon mate accidentally discharge an M-79 on patrol in the Central Highlands of Vietnam back in 1965 or 66. They were travelling through thick brush and the safety had come off and the trigger had been pressed. He remembered the sound of the round sailing through the jungle canopy straight through the air. It landed right in front of him, it was spinning but it had not armed! He lived another day.

    He was a very lucky man!

  12. I’ve spoken with a number of past and recent SF operators, apparently they still use the old girls. All praised the accuracy, several claimed to be able to hit windows out to 500m. Now all I need to do is win the lottery!

  13. I think Ian needs to do some more research on the origins of this weapon.

    For one thing, the bazooka was a direct-fire weapon; the M-79 and 40mm grenade were meant for indirect fire. The roles are NOT interchangeable, at all.

    I think the poster who said that the correct antecedent for this weapon would be the Japanese “knee mortar” is probably way more “right” than saying it came from the bazooka. A lot of the issues that this weapon was meant to address were things like the dead areas encountered for direct-fire weapons like the MGs in Korea; at the squad level, there simply wasn’t any way of getting any fires into the dead zones, so this was the solution. Along with the Claymore, but that required a bit more setup, and was only good for a single shot into said dead zone before you’d have to set up another.

    All in all, the real wonder is that it took as long as it did for the US to begin addressing the issues that the 40mm grenade launcher and Claymore addressed. I still find it hard to believe that nobody thought to produce what amounts to a factory-made fougasse until the 1950s–We’ve only been doing the fougasse since the advent of black powder, and it was probably the direct ancestor of the cannon. So, why did we take so long to develop its conceptual descendent? I look at WWI battlefields, and I’m like “So… This’d be a perfect place for a Claymore or two…”. Plus that, they had actual “land torpedos” in the Civil War that were electrically fired, so it’s not like the idea never occurred to anyone.

    Frankly, I look at the whole thing as yet another example of the essential “unseriousness” of the military class in general–The Claymore concept should have been implemented during the Russo-Japanese War, for cryin’ out loud…

    • “example of the essential “unseriousness” of the military class in general”(C)

      The military are the same children.
      Only the machines are real and the pussies are hairy. 😉

    • Yeah, but as for the Russo-Japanese War, the Russian soldiers defending Port Arthur from land-based Japanese assaults looked at what they did have (concrete walls, barbed wire, artillery, and heavy machine guns) and concluded from the failed attacks that the Japanese were not intelligent enough to require the Russians to invent a new weapon to kill them. “After all, they all die with swords or bayonets in hand when shot from very far away, no need to waste our time inventing another way to kill WORTHLESS yellow monkeys.”

    • Kirk – From 1945 to June 1950, the US Army was given almost no funding for new equipment and what little there was went to R&D. After we had the Bomb, there wasn’t going to be any more land wars. (As a cadet I did a book report on “The Weapons of World War III – the Long Road Back from the Bomb” by John S Tompkins published in 1967 which explored this and how long it took to recover from it)) So the US Army was undermanned, undertrained and under equipped when Korea broke out. The first several years of Korea had the Ordnance Corps struggling to refurbish enough weapons and equipment to equip an unexpectedly enlarged Army in both Korea and Germany, let alone develop, produce and issue mew equipment. Norman Friedman’s Iron Law of Mobilization states that in an emergency, you produce what you are already building, because attempting to introduce something better costs too much in terms of volume and time

      “The iron law of mobilization is that you build what you have been building – or else suffer brutal and unpredictable delays” – Fighting the Great War At Sea

      “…the Royal Navy had to continue to produce existing weapons and fire control systems, whatever their deficiencies, the iron law of mobilization is that you produce what is on hand – you do not wait for something better” – Naval Antiaircraft Guns and Gunnery

      “The Come as You Are War” – US Army slogan in the 1970’s based on the Yom Kipper War

      “You go to war with the army you have, not the army you might want or wish to have at a later time.” – Donald Rumsfeld

      • You speak truths, but they’re really (and, sadly…) utterly irrelevant. No matter the conditions, the Army and other branches still had a duty to prepare for conventional war. They failed to do so, deludedly thinking that the advent of atomic weapons meant they’d become irrelevant. However excusable that might have been, there still should have been some contrarian “Hey, what if we’re wrong about all this…?” thinking done, and the proper reports to Congress made, along with some moral stands being made. Nobody made the effort, did they?

        It’s just like with the Vietnam debacle. The generals later claimed they’d advised against it all, but where were the resignations? Where were the stands taken, against what Johnson and the rest were ordering? Were any of the misgivings they later described in their memoirs ever voiced?

        Similarly, where the hell are the resignations over the Afghanistan BS? How is it that we’re paying the Pakistanis to pay the Taliban to kill American troops in Afghanistan? The whole thing is a kabuki dance–We all know where the money and support are coming from–Hell, we killed bin Laden in freakin’ Abbottabad, which is about like finding him next door to West Point, in terms of what that city is to the Pakistani military.

        So… Yeah. I’m not at all OK with excusing the incompetency of it all. The geniuses are still at it, today–Look at the disgraceful speed we’ve returned to “normality” after learning all the lessons of modern warfare, like recognizing that there are no “rear areas”, and that we’ll have to provide hardened security forces for everything moving between what we’re actually standing on. Instead of making Personal Security Detachments a permanent part of the MTOE, providing the manpower and equipment for them, we’ve stood them down and are making believe we’ll never need them again. Until next time, when we’ll strip the manpower and equipment out of the line units which are being pared down past bare-bones yet again.

        I can hear the excuses already, and as a retired professional soldier, I don’t want to hear them. As a soldier, you have a duty to prepare. Period. Politicians don’t want to pay for it? Too bad–The right thing to do is fall on your sword, and make the same point that Douglas MacArthur was going to make if FDR went through with his Depression-era cuts. I haven’t seen any of our flag ranks willing to make that same sort of sacrifice in the last seventy years, and there have been multiple occasions when they damn sure should have. The post-WWII era was just the first time, for both needing to do that, and utterly failing in their duty to the nation and the troops.

        • “(…)should have been some contrarian(…)”
          There was NSC-68 dated April 1950 which pointed need for means not being total war https://en.wikisource.org/wiki/NSC-68
          IV. The Underlying Conflict in the Realm of Ideas and Values Between the U.S. Purpose and the Kremlin Design
          …”The means to be employed must be proportioned to the extent of the mischief.” The mischief may be a global war or it may be a Soviet campaign for limited objectives. In either case we should take no avoidable initiative which would cause it to become a war of annihilation, and if we have the forces to defeat a Soviet drive for limited objectives it may well be to our interest not to let it become a global war. Our aim in applying force must be to compel the acceptance of terms consistent with our objectives, and our capabilities for the application of force should, therefore, within the limits of what we can sustain over the long pull, be congruent to the range of tasks which we may encounter.

          IX. Possible Courses of Action
          …This is largely a problem of the incongruity of the current actual capabilities of the free world and the threat to it, for the free world has an economic and military potential far superior to the potential of the Soviet Union and its satellites. The shadow of Soviet force falls darkly on Western Europe and Asia and supports a policy of encroachment. The free world lacks adequate means–in the form of forces in being–to thwart such expansion locally. The United States will therefore be confronted more frequently with the dilemma of reacting totally to a limited extension of Soviet control or of not reacting at all (except with ineffectual protests and half measures). Continuation of present trends is likely to lead, therefore, to a gradual withdrawal under the direct or indirect pressure of the Soviet Union, until we discover one day that we have sacrificed positions of vital interest. In other words, the United States would have chosen, by lack of the necessary decisions and actions, to fall back to isolation in the Western Hemisphere. This course would at best result in only a relatively brief truce and would be ended either by our capitulation or by a defensive war–on unfavorable terms from unfavorable positions–against a Soviet Empire compromising all or most of Eurasia….

          For more data about limited warfare consideration read https://apps.dtic.mil/dtic/tr/fulltext/u2/a215572.pdf

  14. During all those efforts to improve on the M79, why didn’t somebody think of a pepperbox layout? It would look like the old Stevens 4-bbl pistol grown huge and fitted with a stock. Double action, naturally. Yes, it’d be bulky, but not overly heavy (aluminum is wonderful stuff) and would enable a quick 4 rds to be laid on a target as fast as a man could aim. Now imagine a simple (maybe expendable) speed loader, and bloop’s your uncle. Oh yes: the barrel group pivots sideways rather than vertically, to allow those extra-lengths to be loaded. Keep the lockwork bonehead simple and fit all the fancy sights you like. Hey, it +might+ work.

    • “..why didn’t somebody think of a pepperbox layout? ….would enable a quick 4 rds to be laid on a target as fast as a man could aim.”

      Because it was 6.5 lbs loaded with one shot, each round was another 1/2 pound, bringing your 4 shot weapon to over 8 lbs, probably closer to 9 or 10 lbs with the increased weight of the extra breech and trigger and locking pieces required to add and then sequentially fire the extra barrels. Not to mention the reliability issues of the increased complexity.

      Besides, when there were green tracers in the air, no one was holding still long enough to pop off 4 aimed shots on that tube. You shot, you ducked and reloaded, possibly shifted position a bit, adjusted aim and shot again.
      Not to mention, how many rounds was a load out? You put 4 rounds down range fast…and how many rounds do you have left?

      Neat idea for COD, but IRL, lots of issues are raised.

  15. The M79 was not normally an Indirect fire weapon.

    Indirect fire means the shooter has no view of the target and must get directions “indirectly” from another observer. Typically Indirect fires ARE High angle fires.

    The M79 was a “High Angle fire Weapon” used in “Direct lay” that is the shooter observes the target to make his own corrections.

    Technically many would argue that all fire originating at less than 45 degrees angle above horizontal are “Low angle Fires” and when using the sights on an M79 by that definition it is a low angle weapon.

    Using the “Marked Sling” method the M 79 was fired at High Angle, as described above from a kneel usually and with the Butt on the ground. Using a gunners quadrant from an artillery piece or tank the Grenadier would fix his sling to a known length, mark the lock for that length. then place his foot on the sling and elevate the muzzle until he got the reading he wanted on the Gunner’s Quadrant, then marked the sling.

    One would get three or four known marks for given range and angle and then SWAG (Scientific Wild Assed Guess) for targets in between those known points. Aiming was done by aligning the barrel so it pointed at the target. Notice the gunner still observed the target.

    It was possible in a defensive position to use the Marked Sling Method to engage unseen targets in true Indirect Fire via marking a spot for the butt to rest on the ground and using aiming stakes to allow one to fire on preselected targets and again SWAG a shot at something a different observer described based on its location from the pre plotted target.

    Firing at high angle was not to be done closer than 90 meters as time of flight at such a high angle exposed the grenade in flight to wind for a considerable time meaning it could drift, perhaps even back to the Grenadier or his friends.

    No doubt there were high angle shots like made in “A Porkchop Now” but a hit would have been very much an “op-slop, bring the mop” article of luck mostly and in that scene likely violate that 90 meter minimum range, making the shooter not your friend.

    Though I never saw anything official on it, I saw an M79 with a Rifle Grenade launcher sight as used on the M1 rifle and Carbine and the M14 rifle. It has a level and marked click adjustable elevations and would have likely been better than the Marked sling, though fragile ( like the good sights on the M203)

    There were a number of grenades besides the HE with its pre notched wire fragmentation system. There was the HEDP (HE Dual Purpose)which had a HEAT (High Explosive Anti Tank) charge also wrapped with a frag collar. I was rated at piercing 2.5 inches of steel armor, enough for IFV, APC, and Recon vehicles. There was also a round with a very small initial charge and a delay on the main grenade that was basically a long range “Bouncing Betty” the round would strike then be tossed about two meters in the air and airburst.

    All those were fielded while the M79 was still in common use and continued to be used with the M203.

    Where folks missed the M 79 was in the delivery of long shells like the large flare that was a bit better than hand launched flare and had various types available for signaling or illumination. Also a long CS or CN riot agent round.

    The most common shotgun round only had eight pieces of 00 buck (less than some issued 12 gauge) and a muzzle velocity of only 400 FPS rather than the 1200+ of a 12 Gauge GI 00 load.

    I liked the M79 more than the M203 on the range… but with my life on the line the M-16A1 attached to the M203 made it more comforting

    • Y’know… You’re absolutely right.

      However, I think you’re over-egging the pudding with regards to it being what we should consider a direct-lay weapon, one where you observe the target. The way I understand what they were writing about the initial development, and how I saw the 40mm being used was that the weapon was envisioned to address those areas you could not reach with direct-fire weapons–The deadspace under your MG fires. The impetus came out of Korea, where you’d often find yourself dealing with terrain that enabled the enemy to sneak up on you safely through things like river bottoms, which you could not address effectively with your direct-fire weapons at the squad and platoon level. However, without having to resort to things like a gunner’s quadrant, you can drop rounds all day long into those bits and pieces of terrain you can’t otherwise cover, and yet which are too minor to be able to get mortar or artillery support to address.

      Frankly, we never had too damn much use for a 40mm in the direct-fire role; the place I always put it was where there were avenues of approach we couldn’t cover with MG fire, but which we could deny the enemy use of through the simple expedient of dropping 40mm on them. A lot of the time, that would have meant putting rounds into things like creek bottoms we didn’t have direct observation on, and just doing that “on spec”, or when we thought the enemy was in them.

      Couple of times on exercises in Korea, you’d be able to observe the ROKA guys doing a light infantry infiltration on you, and watch them enter a dry riverbed that led to the front of our defense positions. Usually, what you’d do in that case was wait until you heard noise in the area where that was, and then tell the exercise umpire you were dropping simulated 40mm fire into the riverbed with the ROKA guys… Typically, the dice would get rolled, and you might or might not be granted casualty effects by doing so. In real life, though? That was what we used the M203s for, and how we used ’em. I honestly can’t remember ever putting together a defense plan where the M203 was supposed to be doing anything direct-fire. At. All. Wasn’t a point to it, when you always had so much dead area to cover.

  16. It is, in general, a very flexible platform.
    They did a lot for him.
    Starting with a package of seven 22lr barrels, continuing with silent shots and ending with a drone.

  17. When my unit, a company of 2bn 5th marine Regiment deployed to Iraq in 2007, two M79 launchers came in to our possession. At the time I assumed theses were issued from old stockpiles, although I do not know that to be a fact (we also had M72 LAW rocket launchers, which at the time I thought was old stuff but after a little research, I see that they may have been new manufacture). Either way they saw no to little use. One was placed in the control of whoever was the current corporal of the guard at the combat outpost (cop) that my platoon lived at. As the cop was never attacked (at least while I was there) the only (rumored) use was to fire off illuminating rounds on the 4th of July.

  18. Just for interest, about 50 years ago I was a medic in Viet Nam. One day we got a woman who had been hit in the lower abdomen by an M79 grenade which did not detonate. As she was still alive with it lodged inside her, a surgeon sandbagged her up, put on a steel helmet and flak jacket and (very carefully) removed it. Maybe the fuse had not armed, but who knows! I was happy not to participate personally! And I remember another lady who was hit in the face by shrapnel from an M79 – not a pretty sight.

  19. I qualified while working for the State of Texas on a variant made by Smith &Wesson as a tear gas launcher. Gas and bean bag rounds. On the original M79, I met a number of artists who could get first shot into openings when needed. Good memories

  20. I knew a man who was a LRRP in Vietnam. He told me that he had a M79 cut down to be even more portable. He told me that a M79 was a real ace in the hole when you got pinned down, and needed to break out. He had a M16 as a main weapon, and cautioned against carrying it on full auto when walking point.

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