The rifle grenade is almost entirely missing from the mind of the American servicemember or weapons aficionado. That’s because of project SALVO, which went nowhere but did give us project NIBLICK which begat the 40x46 hi-lo 40mm cartridge and eventually the M79 (it took a while to get a useful launcher) around 1961.
The 40 mm launcher has taken over the throw explosives over there role worldwide for some convenience, and a lot because of my usual argument for the prevalence of the M4/M16: the US became the only superpower. Plus things like consolidation destroying many entire national arms industries, the easy choice becomes “buy whatever mature system the Americans make.”
40 mm is fine, but the one bad thing it has caused is a lack of imagination. We think rifle grenade technology stopped being developed in 1954 so Korean War rifle grenades are what is being talked about. No one even considers what else is possible, far too often.
The Mythology of Rifle Grenades
- Inconvenient — You have to carry blanks. Turn off the gas system, maybe change other things about your gun to fire
- Needs a launcher — In fact, that you can't just shoot them off the muzzle then, but you also have to carry the grenade launcher adapter and first mount it on the end of the rifle first
- Dangerous — If you use a live round instead of a blank, that will ignite the grenade and blow you or your squad up. This is not just a danger but a fear so troops ca be reluctant to use, or flinch more.
- Ruins the rifle — If a bad guy pops up close you can’t shoot them with your rifle.
- Recoil — Use it wrong and they knock you down or dislocate your shoulder.
- Heavy — Rifle grenades are huge and heavy.
The MAS49/56, the french service rifle more or less from the post-war rebuilding until the FAMAS, had a standard 22 mm lug and a gas cutoff system integral with a grenade sight. The earlier MAS49 had a grenade launching adapter as well.
The Truth of Rifle Grenades
So one by one, let's discuss each of these points:
Inconvenient
Nope, they don’t use blanks anymore. Most rifle grenades are what is call the Bullet Trap style. Exactly what is printed on the tin, there’s a trap, you fire live ammo and the gas AND bullet impact force are used to propel the grenade. Some — like the TELGREN and the JAPANESE WHAT??? are Bullet Thru, which also is entirely explained. Self- sealing hole down the middle, snags all the gasses and I presume a bit of bullet inertia also. Means you can’t accidentally use some AP round that might go through the trap but mostly lighter weight, as no trap. It does make the payload design hard, apparently, as you can imagine.
Needs a launcher
Nope. Not a thing. I mean, maybe for commies but let me introduce you to:
...the 22 mm muzzle device.
You ever noticed how all NATO rifles have the same diameter muzzle device? G3, M16, same basic outer shape. Why? Rifle grenade launching. Sure, dedicated orgs like the French have additional stabilizers back on the barrel for /better/ grenade launching, but all normal rifles, with normal muzzle devices, can launch normal rifle grenades for like 50 years. Grenade launching adapters are not a thing.
Dangerous
No such thing as explained above. So blanks needed so normal ammo will do fine. Safety has increased for ordnance generally so if somehow you shoot an API round it still should not ignite the grenade primary charge.
Ruins the rifle
Besides being old (no adapters, no gas system shut off anymore) this is an armchair commando comment because in wars what do you bring: All you friends with their guns. See this guy walking around with a rifle grenade mounted? Because he’s got friends with rifles without grenades mounted.
Also, how’s an M79, M320, or even just the weird grip of an M203 give you the instant ability to shoot someone with a rifle? Even if you notice (aiming at someone far away, etc) my favorite solution in the very unlikely case this comes up: shoot em with a grenade!
Recoil
Again very old information and also sort of irrelevant. If you are a WW2 soldier with a big adapter and heavy steel rifle grenade you also had what they call Training. You know this essentially turns your rifle into a mortar so you place the butt on the ground. 50s-60s soldier? You are told to let it free recoil. Hold it at the waist and not let the butt touch anything.
And in both these cases, hard to forget as the grenade sights don’t work if you try to shoulder it anyway! But today, no danger. Mostly because the grenades are amazingly light. Some lighter than an M203 round. You know recoil is mass+speed so light rounds going not that fast is not that much recoil. The plastic construction also is like plastic stocks vs wood on a shotgun; they flex and soak up recoil. Yes, that works. The heavy payload end being squashily attached to the gun spreads out the recoil impulse to the gun, then, to your shoulder.
A Marine tries launching a rifle grendade off a FAMAS. This is someone unexperienced, at full recoil. He's just fine.
Some appear to have elastomeric attachments and the TELGREN telescropes. You extend it to fire, but on firing it collapses back down, which is super duper spreading out the recoil impulse over time.
Weight
Again, old data, like saying all American guns are heavy compared to modern Chinese guns and using a BAR as an example. Exactly the same. Modern rifle grenades are crazy lighweight, and as compact as they can be so easy to carry.
Things Rifle Grenades Excel At
Mostly, being spigot launchers. Fundamentally, that’s the most important one to me. You are’t restricted to things that fit into a barrel, the requirement the outside of the projectile be able to handle in-a-barrel forces, or carry around a cartridge case or otherwise propellant to launch that.
So, rifle grenades are available in different formats, like HE or AT. Flares and smoke. BIG flares; need some illum? You can parachute flare rifle grenades with similar properties to 60 mm parachute illum.
You can do really weird things. I can’t find one this moment, but “Ambush Breakers” used to be issued to a few armies. A rifle grenade, but it doesn’t launch. Instead it fires a claymore-like wide-dispersion shotgun blast off the end of your rifle! No special weapon system, just second in line in your jungle patrol has this mounted and is part of the immediate action drill.
A favorite of mine I SIMON, adopted with minor safety changes by the Army as the M100 GREM. It fires a moderately low-explosive charge at standoff, so you can knock down doors entirely, and with a reduced chance of destroying the whole room (and all occupants) beyond. Wide, long, odd shaped. Don’t need to make a new giant launcher for it as it’s a rifle grenade. Just stuff on the end of your M4.
The French and Japanese (two who issue rifle grenades to their entire armies) both use HEDP rounds. They blow up and can destroy equipment and kill troops in the open, but also have a shaped charge that is large enough in diameter they can defeat armor of anything short of a fairly modern tank.
A 40 mm can't do that no matter how hard it tries. HEAT warhead penetration is a function of diameter and 40 mm simply isn't big enough around.
Rifle Grenade or 40 mm?
A lot of this is about mindset. How does your army want to work. Like claims the MG42 is better than the 1919 or BAR are… asking the wrong question. They were each fine for the ways the armies worked, and switching guns would have been bad.
The US seems to like having grenadiers. IF we’re fine with 40 mm payloads, that works then because they carry what like 2 dozen grenades? But what if you don’t like grenadiers, and want most of your squad to have the ability to fire explosives to 300 m range? Then, rile grenades are a much better choice than a grenade gun.
Similarly, rate of fire is often brought into the conversation, for the relatively fast reload speed of M203/320, and the immediate firepower of the Milkor MGL (M32A1-MSGL in US service, finally), but of course it's the same conversation. If only one person is firing grenades, then their firing speed matters; if the whole squad is firing, then you can either mass fires or have everyone fire serially with discussions of wind and range, to adjust fire for each follow-on shot in the same way.
Weight alone, you can carry 10-11 Telgren (for example) for the same weight as 10 M203 and an M203PI. Over that load, the M203 gets the benefit. Under it, the rifle grenade.
Then it’s how you approach it. If you like having a grenadier designated, then a standalone 230 or Milcor with 36 rounds on him is likely a good idea. If you want everyone to be able to lay explosives, then everyone with 1-3 rifle grenades is good… OR, mix and match. Which is what we’ve lost with so so very much emphasis on the 40 mm. Why not have both, so you can carry not just breach grenades, but redefine what “organic” fire support means and bring bigger boom, smoke, or illum to the platoon or squad level.
Future Concerns — Suppressors:
Since I like to think systems, one issue that is going to be arising is suppressors. French love rifle grenades but I have also see whole platoons issued with small suppressors.
They may bring us back to all grenade guns or maybe… adapter like issues? You can’t shoot rifle grenades from suppressors or brakes. This seems solvable though, for example just put a 22 mm flash hider on the end maybe? But, worth keeping in mind if planning on equipping your army with rifle grenades as you may also want some to be suppressed.
Polyvalents:
An idea that was actually fielded for a while in the 70s was the polyvalent grenade. That is just a big word that means it's configurable and multi-mode.
See?! You can carry a hand grenade, and add a tailcone to it, now it's a rifle grenade. There are a number of other multi-configuration grenades around, like those with removable fragment sleeves, and now there are a few that are stackable to change how much they go boom or even become Bangalore torpedoes. So... it makes me wonder if things like this may come back some day.
A similar French one spanned the introduction of the bullet trap and became suddenly 2" longer with a big, obvious steel trap screwed between the tail and grenade. While it was a bit clunky, it also points to another value both rifle grenades in general can have, and polyvalents specifically: they can be any shape so things like this can be done.
Other Photos:
Too much to choose from for the article above, so I tossed more of them down here.