The HORRORS of the M79 Grenade Launcher at Firebase Burt

It is just past midnight on the 1st of January, 1968. At a raw firebase called Burt, 7 miles from the Cambodian border, dug only 3 days earlier, 2,500 Viet Cong are coming through the dark in waves. There’s a strip of ground out past the sandbags, too close for the big guns to touch without killing the men in the foxholes, too far for a thrown grenade to reach.

 And in that strip, the enemy is massing. Then, from the trench line, a sound answers them. Not a rifle, not a machine gun, a hollow, almost gentle thump. A 40-mm high-explosive grenade arcs up over the wire and drops straight down into the crawling mass. A flat orange flash, 300 fragments tearing outward in every direction. Thump. Another. Thump.

Another. This is the M79 grenade launcher. The men called it the thumper. And in the dead ground at firebase Burt, it did the close-in killing that nothing else could reach. To understand why one man with a 6-lb tube mattered that night, you have to understand the trap the Americans were sitting in. Pope Paul VI had declared the 1st of January a day of peace.

 The South Vietnamese agreed to a truce. So did the Viet Cong. A 36-hour ceasefire announced out loud to the world. That morning, the men of the 25th Infantry Division got their Christmas mail. It had finally been flown into the new landing zone. They spent the day of peace opening packages from home. A chaplain, Captain Jim Tobin, gave communion on the firebase.

 Burt was 3 days old. It sat in War Zone C in Tay Ninh Province, astride a road network that funneled enemy supplies down out of Cambodia towards Saigon. Two battalions held it. The 3rd Battalion, 22nd Infantry. The 2nd Battalion, 22nd Infantry Mechanized. Their guns came from the 2nd Battalion, 77th Artillery.

 They called themselves the triple deuce. The jungle around them was thick. The foxholes were hasty. The fields of fire were short, and the enemy was already at the edge of the wire watching. On the evening of the 31st of December, a listening post from Company A, 200 m out in the black, reported movement all around it. The men blew their claymore mines and threw grenades into the dark.

The movement stopped. The next evening, an ambush patrol moved out east of the perimeter and walked straight into fire from a force they never saw. Two men killed, one wounded. The patrol fell back inside the wire. That was the probing, the hand being shown. Six hours before the truce was set to expire, two regiments of the Viet Cong 9th Division, the 271st and the 272nd, closed the trap.

The weapon that would hold the dead ground had only been around for a few years. It came out of an army program called Project Niblick, an effort to give an ordinary infantryman his own explosive punch, more accurate than a rifle grenade, more portable than a mortar. Springfield Armory built it as a single shot break-open weapon that looked like an oversized sawed-off shotgun, and the army standardized it in December of 1960.

The clever part was never the launcher. It was the round. A 40-mm grenade left the muzzle at only 75 m a second, slow enough that a grenadier could watch his own round arc through the air and walk it onto a target. It reached out to 150 m against a point target, 350 against an area, and when it landed, it burst into roughly 300 fragments with a kill radius of 5 m.

 One man, one tube weighing 6 lb, the explosive reach of a small mortar riding on his shoulder. The troops gave it names, the thumper, the blooper, the bloop tube. The Australians called it the wombat gun. But the name that mattered was the one that described what it did. They called it the platoon leader’s artillery. It was carried by a single dedicated grenadier in each squad, usually a specialist four.

Because the launcher ran 29 in long, he often couldn’t carry a rifle as well. His backup was the 45 on his hip. When the listening post started reporting movement in the days before the attack, the thumpers were among the first weapons to answer, lobbing high explosive out into the tree lines, searching the dark where a rifle could see nothing.

One of the men in those foxholes was a 21-year-old rifleman in Bravo Company, 3rd Battalion, 22nd Infantry. His name was Oliver Stone. He had been in country since September, and he would carry something out of this firebase that he would spend the next 20 years not entirely sure had been real. At 23:30 on the 1st of January, the mortars came first.

Then the ground attack hit the northern edge of the perimeter and rolled south. By 1 minute past midnight, it was everywhere. The main force came down the west side of the road and slammed into the mechanized infantry. Almost in the same instant, rocket-propelled grenades, machine guns, and small arms tore into the southern line.

 And the heaviest weight of it peeled east, straight onto Company C. The attackers were smart about it. They came up the drainage ditches that ran along both sides of the road using the cut earth for cover, crawling closer and closer to the wire. That was the killing ground. The band too close for the howitzers, too far for a thrown grenade, and that is where the grenadiers went to work.

From the company C foxholes, the thumpers began arcing 40-mm high explosive up over the sandbags and down into the ditches. A man couldn’t see much in the dark. He didn’t need to. He knew where the ditch was. He knew the enemy was in it. He set the round to fall where they were crawling and he fired. Thump.

 And broke the breach and loaded another and fired again. Five, maybe six aimed rounds a minute. Each one 300 fragments into a confined trench packed with men. It is worth being precise about what that did. A high explosive air burst over a drainage ditch does not produce a clean death. The fragments fill the cut from wall to wall.

 There is no posture that escapes it. The ditch that had given the attackers cover from rifle fire became the very thing that trapped them under the grenades. By 2:00 in the morning, company A had lost radio contact with its forward platoon. Two or three of the enemy were inside the perimeter. By half past 2:00, the company C ambush element reported half its men down.

And then the artillery did the thing that truly defines this battle. The howitzer crews of the 77th dropped their barrels level. The 105s fired beehive, canister rounds packed with thousands of small steel darts, directly across the company C perimeter over open sights into the massed infantry. When the beehive ran out, they loaded high explosive and fired it flat into the dark.

The bigger 155s did the same across company A. The fire was so constant that the reserve recon platoon could not even move up to reinforce company C. The wall of flechettes sweeping that ground would have killed them, too. So, the geometry of it was simple and it was merciless. The big guns firing flat, sealing the open approaches.

 The grenadiers in the foxholes lobbing high, sealing the ditches the guns couldn’t safely reach. Between the two, there was almost nowhere left to live. It was somewhere in this stretch that Oliver Stone nearly died. A friendly F-4 Phantom working the enemy that was now inside the wire dropped a 500 lb bomb close enough to throw Stone into the air and knock him cold.

 He got up. He walked back to the line. He said later he never fired his rifle the entire night. At some point in the chaos, the concussion of a beehive round burst his eardrum and left him deaf in that ear for the rest of his life. Because he stayed on his feet and never went to an aid station, it never even counted as a wound.

He described the force of that night in four words, like being in a hurricane. There were small, terrible stories in every position. By one veteran’s account, near a quad 50 machine gun mount that was being overrun, the gunner had part of his hand shot away and kept loading and kept firing. The four barrels hammering into the dark.

The 16-man ambush patrol that had been caught outside took the worst of it. By morning, one man was dead from enemy fire, 11 were wounded, and one more had been killed by the friendly air strike called down on top of them. An assistant patrol leader said only three of them came through that night untouched.

 Around 5:00 in the morning, the Viet Cong began to pull back into the jungle, dragging away what wounded they could. By dawn, it was over. The enemy’s own tactics are the highest praise the M79 ever received. The Viet Cong did not come up those ditches out of carelessness. They pressed in close on purpose. Their entire method that night was to get inside the range where American firepower became too dangerous to use, to grab the defenders by the belt and hold on so the howitzers and the jets couldn’t swing freely without killing their own men.

The grenade launcher was one of the few things that still worked inside that embrace, but it had a hard limit, and honesty demands it be named. That 40-mm round has to spin a set number of turns before its fuse arms. Until it has traveled about 30 m, it will not go off. So, when the enemy clawed all the way to the wire inside that 30-m line, the thumper went quiet.

 The round became a slow steel ball. At that range, the grenadier had nothing left but the 45 on his hip and whatever the men beside him could bring. The same closeness that the M79 punished out in the ditches could also beat it at the wire. That was the brutal arithmetic the enemy was betting on. The thumper was never only an American weapon.

 Australian infantry in Phuoc Tuy province carried it, too, and gave it their own name, the wombat gun. In February of 1970, a section commander named Corporal Joe Daneluk of the 8th Battalion, Royal Australian Regiment, was photographed carrying his M79 through the bombed-out scrub of the Long Hai Hills, his rifle slung across his back, after days of close fighting.

Different army, same 6-lb answer to the same old problem, the gap between the grenade you could throw and the mortar you had to call for. When the sun came up over Burt, more than 400 enemy dead lay around the perimeter, many of them piled in the ditches. 23 Americans had been killed. 153 were wounded.

 Oliver Stone was among the men sent out to gather the enemy bodies for burial. Years later, he would write of charred figures frozen in the positions they died in, of white napalm dust on gray trees. For a long time after he got home, he wasn’t sure any of it had happened. There had been almost nothing in the newspapers.

 It was only at a reunion years later with other men who who been there that he knew he hadn’t imagined it. In 1986, he put that night on a movie screen, and the final battle of the film Platoon showed the world what the men of the Triple Deuce had lived through. Another man who fought there, Larry Heinemann, became a novelist and spent years writing his way back through it.

The grenade launcher itself was already on its way out. Its single-shot reload was too slow for a long firefight, and within a few years the Army began replacing it with the M203, a launcher that clamped under a rifle so the grenadier could be a rifleman again. Special operators still reach for the original even now for its reach and its accuracy.

But the men who carried it remember it by its sound, that hollow thump in the dark. The slow grenade you could almost follow with your eye, rising up over the wire and falling into the one place the guns could not go. At Firebase Burt, on the night the truce was supposed to hold, that sound was the difference between the ditch and the perimeter, between the line breaking and the line holding.