The HORRORS of the M3 Grease Gun in Vietnam

April 30th, 1967. Hill 881 South near Khe San. Marines from Hotel Company, 2nd Battalion, 3rd Marines are being cut to pieces by entrenched North Vietnamese regulars. Their brand new M-16 rifles, the most expensive small arm the Pentagon has ever issued, are jamming. Men are shoving cleaning rods down their own barrels in the middle of the firefight trying to knock empty brass out of pitted chambers, trying not to die.

By sundown, nine Marines from Hotel Company are dead. 43 more are wounded in a single day. But not every American on that hillside is dying with a jammed rifle in his hands. Some are still firing. They’re carrying a stamped steel relic from World War II, a weapon the Army officially considered obsolete, crude, ugly, slow, built to cost $20.

94, barely the price of a steak dinner in 1943. It looked like a mechanic’s lubrication tool, so that’s what the men called it, the grease gun. And in the mud and tunnels and tank turrets of Vietnam, this $20 piece of stamped junk would do something the $126 high-tech M-16 could not.

 It would keep firing every single time. The gun was designed in 1942 by a man named George J. Hyde, a German immigrant machinist, chief gun designer at General Motors Inland Division. Frederick Sampson, GM’s chief engineer, helped him. Colonel Rene Studler of Army Ordnance signed off on the project. The Army adopted it on December 12th, 1942.

The job was simple, build something cheaper than the Thompson, faster to manufacture, a weapon America could mass produce by the hundreds of thousands while the Wehrmacht was rolling toward Moscow. The result was a tube of stamped sheet steel, .060 inches thick, two halves welded together. Only the bolt and barrel were precision machined.

Everything else was scrap metal simplicity. Guide Lamp Division in Anderson, Indiana, a plant that had been making car parts the year before, was now building submachine guns. The grease gun fired the .45 ACP cartridge, a 230 grain slug, subsonic, heavy, brutal, moving at roughly 920 feet per second.

 The cyclic rate was just 450 rounds per minute, half the speed of a Thompson, a quarter of what a German MP 40 could spit out. There was no semi-automatic setting, no safety lever. The dust cover over the ejection port acted as the safety. You opened it, you pulled the trigger. It fired until the magazine ran dry, a spray and pray weapon for tank crews who might have to bail out of a burning Sherman and fight on foot.

 That was the original idea anyway. By the end of World War II, GM had built 622,000 of them. By 1957, the Army considered the grease gun obsolete. By 1965, it was supposed to be retired entirely. It wasn’t. Because in 1965, the Pentagon issued a different gun to its Marines and soldiers in Vietnam, Eugene Stoner’s masterpiece, the M-16, lightweight, modern, high velocity, a rifle from the future.

 And then it started killing the men carrying it. Stoner had specified IMR powder for the 5.56 cartridge, stick propellant, clean burning. The Army switched it. Olin Mathieson WC846 ball powder, cheaper, dirtier. It burned hotter. It raised the cyclic rate. It coated the inside of the rifle with carbon residue after 100 rounds. The chambers weren’t chrome lined.

 In Vietnamese humidity, they pitted within weeks. The extractor would rip the rim clean off a brass casing on ejection, leaving the empty case welded inside the chamber. And the Army told the men the rifle did not need cleaning, so they didn’t issue cleaning kits. July 2nd, 1967, Operation Buffalo.

 First Battalion, 9th Marines walks into a horseshoe ambush at a place called the marketplace near Con Thien. By nightfall, 84 Marines are dead, 190 are wounded, nine are missing. The single worst day for any Marine battalion in the entire Vietnam War. When the bodies were recovered, some were found with their M-16s broken open, cleaning rods still in their hands.

 They had died trying to clear a jam. Now, think about what that meant on the ground. The most expensive American rifle ever issued at $126.37 per unit was failing in combat. And the men who got their hands on a grease gun were watching theirs work. Mud, rain, dust, tunnels, salt water, it didn’t matter.

 The action was loose, the tolerances were sloppy, the whole design was forgiving in a way the precision-machined M-16 could never be. A speck of grit that would lock up a Stoner rifle would just rattle around inside a grease gun and fall out. The .45 ACP round wasn’t a bullet exactly. It was a flying sledgehammer. 230 grains of subsonic lead that didn’t pierce a man so much as knock him off his feet at 10 ft in a doorway, in a trench, in a tunnel mouth, in the cramped turret of an M48 Patton tank. That was everything.

You didn’t need range. You didn’t need accuracy past 50 ft. You needed a weapon that would keep firing when your life had narrowed down to the next 3 seconds. The grease gun did exactly that. February 1968, the Tet Offensive, the Battle of Hue. First Marine Division is clearing the old Imperial City block by block, house by house, room by room.

 In a pile of recaptured weapons, guns the Viet Cong had stolen from ARVN stockpiles and lost again in the fighting, a Marine combat photographer named Corporal John Pennington spots something familiar. A stamped steel tube with a wire stock made by Ithaca Gun Company serial number 750213. Pennington grabs it, takes five magazines.

 He passes the grease gun to another combat photographer, R.J. DelVecchio, who’s heading out with First Battalion 7th Marines on Operation Pursuit near Da Nang. When the unit gets ambushed, DelVecchio empties a magazine into a tree line. The grease gun does not hiccup, not once. His sergeant pulls him aside. From now on, DelVecchio is rear guard.

 In his own words, “I had the grease gun, which everyone figured was more dependable than our M-16s.” He hands the gun off to a third Marine photographer, Dennis Fisher. April 13th, 1968, Operation No Name II. Delta Company, First Battalion, 27th Marines is in contact with the 804th NVA Main Force Battalion. Fisher opens up with the grease gun, and both sides, Marines and NVA, briefly stop firing.

 Fisher would remember it later as a momentary pause, as if they were trying to process this new sound and decide who it belonged to. That slow, heavy clap of .45 ACP at 450 rounds per minute. Nobody alive in 1968 had heard a gun talk like that on a battlefield since Korea. It sounded like history catching up. Corporal Pennington never made it home.

He was killed in an ambush near Khe San on June 9th, 1968. A novelist who served beside him, Gustav Hasford, would later write a book about the war. He gave his main character a souvenired grease gun. He dedicated the book to Pennington. The book was called The Short-Timers. You know it by the movie’s name, Full Metal Jacket.

 Late January 1968, Route 9, Western Quang Tri Province. Captain Daniel Kent, commanding officer of Bravo Company, Third Tank Battalion, is hit in the turret of his M-48 Patton during an NVA ambush. The tank takes more fire, then more. The crew is exposed. The vehicle is starting to burn. Lance Corporal Harry Christiansen takes over as tank commander.

 He climbs up into the turret with a grease gun in his hands. He doesn’t have time to aim. He doesn’t have time to think. He fires. His crew, ducked down inside the burning tank, loads magazines and passes them up to him one after another. The .45 ACP slugs walking through the North Vietnamese infantry trying to swarm the vehicle. When the count was finally tallied, over 130 enemy bodies lay around the position.

Christiansen was wounded. He survived. He was awarded the Silver Star. For every American tank in Vietnam, every M48 Patton, every M551 Sheridan, every M113 armored personnel carrier, the grease gun was the crew’s last weapon. Racked inside the vehicle on a dedicated mount, the thing you grabbed when your tank was on fire and you had to fight your way out on foot.

 The men called it their bailout gun. It would still be racked in American armored vehicles 30 years later. Soldiers of the 19th Engineer Battalion carried grease guns into Operation Desert Storm in 1991. A $20 gun designed in 1942, still fighting in the Persian Gulf almost half a century later. But the most haunting chapter of the grease gun’s war wasn’t fought in tanks.

It was fought in the dark. MACV SOG, Military Assistance Command Vietnam Studies and Observations Group, the most secret unit of the war. Six to 12-man recon teams sent across the borders into Laos and Cambodia to do things the United States government would never admit to doing. SOG sustained the highest casualty rate of any American unit since the Civil War.

 It also posted the highest kill ratio in United States military history, 158 to 1 by 1970. And SOG carried suppressed M3A1 grease guns. The subsonic .45 round made no supersonic crack. With a 3-lb suppressor screwed onto the barrel, the gun whispered. The slow cyclic rate let an operator squeeze off single shots if he had to, or controlled three-round bursts.

The grease gun was, for years, the only suppressed submachine gun available to American special operators. The most feared SOG operator on the entire planet was a man named Jerry Shriver, Sergeant First Class, Fifth Special Forces Group, Command and Control South, Ban Me Thuoc. Radio Hanoi called him Mad Dog.

The communists put a $10,000 bounty on his head, about $70,000 in today’s money. Shriver refused to carry an M-16. He told other operators, “Them long guns will get you in trouble.” Instead, he carried a sawed-off shotgun, five or six revolvers stuffed across his vest, and a suppressed M3A1 grease gun. He reportedly slept with it under his pillow.

April 24th, 1969, Shriver was sent into Cambodia, a raid on a COSVN command bunker complex near the Fishhook, following a massive B-52 strike. His team was surrounded almost immediately. A radio operator asked Shriver for a situation report. His reply was vintage Mad Dog. “No, no. I’ve got them right where I want them, surrounded from the inside.

” He charged a tree line with the suppressed grease gun in his hands. He was never seen again. His body was never recovered. Master Sergeant Jerry Shriver remains missing in action to this day. The thing nobody tells you about war is that progress is a lie. The newest weapon is not always the best weapon.

 The most expensive system is not always the one that brings a man home. Sometimes, the gun that saves your life is the one that costs $20.94 and looks like something a mechanic uses to lubricate a chassis. Eugene Stoner’s M-16 is rightly remembered today as one of the great rifle designs in history. After the I-Cord subcommittee report of October 1967 exposed the powder switch and the missing cleaning kits and the chrome-lined chambers that should have been there from the start, the fixes came.

The M-16A1 became a reliable battlefield weapon. But for the men of 1965 through 1967, the Marines of Hill 881, the dead at the marketplace, the bodies recovered with cleaning rods still in their hands, those fixes came too late. For them, the answer wasn’t the future. The answer was the past.

 A blue-collar German immigrant named George Hyde, designing in a GM plant during World War II, building a submachine gun out of stamped sheet metal because America didn’t have the time or money for elegance. That man, dead long before Vietnam ever started, kept American boys alive in tank turrets and tunnel mouths he could never have imagined. His gun was crude.

 His gun was slow. His gun was ugly. His gun worked. When Delta Force was activated in late 1977, the suppressed M3A1 was its first submachine gun. The German Heckler & Koch MP5 eventually replaced most of them, but a few Delta operators reportedly held onto their grease guns. The MP5 could not suppress as quietly.

 The Philippine military is still modernizing M3A1s today. Picatinny rails, red dot optics, integral suppressors. They call it the M3 Spec Ops Generation 2. The gun designed in a wartime emergency in 1942 has now served on five continents across nearly a century of combat. It is still being carried into action, a $20 relic outliving every weapon that was ever supposed to replace it.