The company deployed to South Korea in March 1951 and was assigned to the U.S. 3rd Infantry Division for four months, where it was used as a reconnaissance and scouting unit, probing North Korean People's Volunteer Army positions.

Later in the summer, the company was used as a stealth "target acquisition" force, infiltrating Chinese positions and spotting concentrations of troops and equipment for artillery attack.

The company was deactivated on 1 August 1951, and was merged with the U.S. 187th Airborne Regimental Combat Team alongside all other Ranger units.

[3] From then on, the U.S. and UN saw a steady stream of defeats until they had been pushed back to the tip of the peninsula, into a 140-mile (230 km)-long fortification dubbed Pusan Perimeter by August.

North Korean special forces units such as the NK 766th Independent Infantry Regiment had defeated ROK troops and used irregular warfare tactics effectively,[6][7] prompting Army Chief of Staff General J. Lawton Collins to order the creation of an elite force which could "infiltrate through enemy lines and attack command posts, artillery, tank parks, and key communications centers or facilities.

"[8] All U.S. Army Ranger units had been disbanded after World War II because they required time-consuming training, specialization, and expensive equipment.

The 60mm M2 mortars, the 57mm recoilless rifles, and the M20 Super Bazookas were carried on the company M35 2½ ton cargo truck but seldom used.

They were merged into the 187th Airborne Regimental Combat Team to bring them back up to strength with airborne-qualified combat-experienced replacements.

The 187th had been moved to Kyushu, Japan's southern island to take on a (then Top Secret) mission to save the UN negotiators at Kaesong, North Korea.

All of the Ranger officers and top NCO's met in a mess hall at Camp Chickamauga, Beppu, Kyushu, Japan.

[11] The Rangers trained extensively in reconnaissance, long-range patrols, setting up roadblocks, land navigation, camouflage, concealment, and adjusting indirect fire.

In March 1951, the 3rd, 5th, and 8th Companies sailed for Korea, a trip which was fraught with frequent discipline problems as the Rangers continuously got into fights with U.S. Marines on board the troopship while en route.

[11] The 3rd Ranger Company entered action on 11 April, part of a tank-infantry task force conducting aggressive reconnaissance in a wide valley near the river.

CO, Jess Tidwell, riding with the tank Co, called Channon on the radio and instructed him to come up and take control of the 1st and 2nd Platoons.

Fortunately, after about 300 yards of sniper fire from higher on the ridge to their right, they were able to gain cover from a 3–4 foot field dyke, and then joined the 3rd Platoon in the center of the valley.

[11] The company then advanced up the valley under sniper and artillery fire until it located and destroyed a Chinese communications and supply center at the end, before returning to 3rd Infantry Division lines.

In all, they had killed over 100 Chinese in this fight, and the division commanders considered the mission a success in spite of the high casualty count.

"[1] [1] They also picked up the nickname “Cold Steel Third”, when division commander Major General Seoul, who was observing the action with other senior officers, was heard to say, “There go my Rangers.

They like that cold steel.”[11] Despite suffering over 50 percent casualties by this time and with few reinforcements, 3rd Ranger Company remained on the line, and was used as a reconnaissance element for the division.

As the 3rd Infantry Division advanced, pressing gains from the Chinese, the company was used to guard a vital bridge over the Hantan River.

[13] On 19 April, the Chinese conducted a counteroffensive in the 3rd Infantry Division sector, first striking to the east, followed by a feint that struck near the Rangers' position.

The task force was assigned to rescue a group of five 3rd Division tanks that had been disabled 8 miles (13 km) inside Chinese territory.

[13] On 22 April, the Rangers, tanks and engineers conducted another probe of the Chinese positions, to ensure they could not launch a surprise attack on nearby Republic of Korea Army formations.

After two days of intense fighting and foot marching, the Rangers moved to relieve the British troops, despite itself being at only 67 percent strength.

These actions have been viewed by historians as one of few instances where Rangers in Korea were effectively employed, used as a stealthy infiltration force for terrain too difficult for conventional units.

The company spent several weeks in division reserve, and undertook various missions such as convoy security and guarding command posts, as well as surveillance and visiting patrols behind the front lines.

[1] In one of these rearguard actions, the Rangers evacuated a rundown village only to have one member of the unit, Corporal David Rawls, captured by three Chinese infiltrators.

Paired with 3rd Infantry Division's reconnaissance company, an artillery battery and a forward air control party, they became known as "Task Force Ferret."

By this time, however, the front lines in the battle had begun to largely stabilize, and as both armies fortified stationary positions, the Rangers infiltration abilities became unusable.

[24] The 3rd Ranger Infantry Company was awarded three campaign streamers and two unit citations for its service in the Korean War.