The Denver Ordnance Plant in Lakewood produced ammunition during World War II. The plant was the largest federal project in Colorado history before its conversion into the Federal Center, which today houses dozens of government agencies.
The federal government announced plans for a munitions plant in 1940, and Denver entered a competition with other municipalities to host the facility. Thanks in large part to effective booster efforts from the Denver Chamber of Commerce, civic organizations, railroads, and newspapers, in December the US government selected Denver as the site for the plant. Construction began in 1941 in the Jefferson County farmlands west of the city, where narrow West Sixth Avenue intersected with the narrower Howell Avenue (soon renamed Kipling Street). On January 4, 1941, the government awarded its largest contract in Colorado, $122.2 million, for development of land, buildings, and equipment associated with the Denver Ordnance Plant. With an estimated total cost of $25 million, the plant was also the largest contract ever awarded in metropolitan Denver.
Remington Arms would operate the plant. Lt. Col. Carl H. Jabelonsky, Army constructing quartermaster for the Denver area since 1938, was picked to oversee construction. An ordnance expert, Lt. Col. Duncan McGregor, was designated the plant commander. The Detroit engineering firm Smith, Hinchman & Grylls based its design for the plant on a similar facility in Independence, Missouri. The plant was promoted as the largest single industrial construction project in metropolitan Denver and created thousands of jobs at a time when Colorado, like much of the nation, struggled with high unemployment rates.
Efforts to complete the project in record time paid off. On April 16, 1941, the first concrete was poured and on May 27 the first steel frames were erected. On October 25, the ammunition plant was dedicated to great ceremony and fanfare, five and a half months ahead of schedule. Some 200 buildings were grouped according to function due to the explosion risks involved in ammunition production. As a protective measure in case of an air attack, the buildings were constructed at least 800 feet apart from one another. Empty land around the most hazardous building groups provided buffers for accidental explosions and hardwood parquet floors reduced the risks of sparks igniting powder inside. At the center of the complex was the general manufacturing area, consisting of four large buildings for the production of .30-caliber cartridges.
World War II
During World War II, the Denver plant was one of four large factories that Remington Arms operated for the federal government; the company accounted for nearly half of all ammunition produced in the country. E. E. Swensson was appointed to manage the company’s Denver plant and began his duties in March 1941.
At first the government asked the plant to produce 4 million cartridges per day. Fewer than two months after the dedication, however, demand for ammunition increased with the bombing of Pearl Harbor and the United States’ entry into the war. In December 1941, the Denver plant produced nearly 14 million rifle and machine gun cartridges. Eventually capable of generating 10 million rounds of ammunition per day, the plant exceeded all original production estimates. A company publication claimed that the Denver Ordnance Plant produced more .30-caliber ammunition than any factory in the United States and perhaps anywhere in the world. The plant’s ability to achieve such a high rate of production was due in part to it being almost completely automated, a model manufacturing process at the time.
Initially, three types of .30-caliber ammunition cartridges were made in the Denver plant: ball, armor piercing, and tracer. Ball cartridges were designed to be used against infantry; armor-piercing cartridges could penetrate armored vehicles or walls, and troops used tracer cartridges to determine if targets were being struck during night missions. Each completed cartridge consisted of four parts: case, bullet, primer, and powder load. Ammunition made at the Denver plant was used by the infantry (in M-1 rifles and M-30 machine guns), the tank corps, and fighter aircraft.
Growth and Decay
At the end of November 1941, the War Department authorized an additional manufacturing building and necessary equipment. Construction began in early 1942. The new building had a wood frame instead of the steel frames used for the first four buildings. The manufacturing equipment also differed; apparently, Remington Arms management feared that the innovative automated systems in the original four buildings might not meet expectations, so they opted for a more traditional, labor-intensive manufacturing process at the new building.
Production at the Denver Ordnance Plant peaked in the summer of 1943 with an output of 6.2 million cartridges per day. Nearly 20,000 people worked in three shifts around the clock. Most of the labor remained unskilled, and women made up about half of the Denver plant’s employees. Supervisors reported relatively little absenteeism, and the safety record of the plant remained excellent. The Remington Arms contract with the War Department to make .30-caliber ammunition expired on July 31, 1944. Ample production at other plants, along with the increased usage of heavier munitions, rendered continuing operations unnecessary. Parts of the facility shut down in the summer of 1944, while Kaiser and Remington Arms prepared to work on a new, smaller contract for fuses for 8-inch and 155mm shells.
As the war dragged into 1945, additional plans were approved to increase production at the plant. In January Kaiser was awarded a contract to manufacture 90mm shells. That same month, Remington Arms was authorized to double its monthly production of fuses, and General Foods moved into one of the vacant buildings and began packaging C rations for combat use. That summer, 10,000 people still worked at the facility. Although the German surrender in May 1945 resulted in some production cutbacks, Remington Arms won another fuse contract in June of that year. Japan’s surrender on August 15, 1945, brought overnight changes to the Denver plant, as production ceased and layoffs began.
Repurposing the Plant
On October 18, 1945, the Denver Ordnance Plant was declared surplus property and turned over to the Reconstruction Finance Corporation for disposal. By this time, the plant’s proximity to an expanding metropolitan Denver made it a highly valuable piece of real estate. Increased residential and business development in the area assured that the property would not revert to agricultural use. Within the complex itself, some 230 buildings stood with 2.5 million square feet of floor space. The structures alone were valued at $28 million.
Numerous manufacturing firms expressed interest in the plant, but by February 1946, it became clear that the federal government intended to resurrect a 1938 plan to develop an office complex in Denver. The first agency to move in was the Veterans Administration in 1946, followed by the Bureau of Reclamation. Since 1947 the Denver Federal Center—as the ordnance plant came to be called—has evolved into the largest compound of federal agencies outside Washington, DC. By 1992, twenty-seven agencies had office, laboratory, or storage facilities on the grounds. A number of the original buildings still remain, modified for other uses.
Today, the Denver Ordnance Plant complex stands as an impressive legacy of federal expansion in the twentieth-century American West. Though it operated in its original capacity for fewer than five years, in that short amount of time the facility gave a much-needed boost to the local economy while simultaneously making immense contributions to the US war effort.
Adapted from Christine Pfaff, “Bullets for the Yanks: Colorado’s World War II Ammunition Factory,” Colorado Heritage, 12, no. 3 (1992).