Savage was one of six companies to participate in the United States Army trials for a .45 caliber semi-automatic pistol, and was named one of the two finalists before losing out to Colt's design, which would become the M1911 pistol. Savage marketed a series of .32 and .380 caliber pocket pistols, the Models 1907, 1915, and 1917 based on the same patents as their .45 caliber prototype.

Savage merged with the Driggs-Seabury Ordnance Company during World War I and produced Lewis machine guns at Driggs-Seabury's former plant in Sharon, Pennsylvania. Savage also produced Model 1899 muskets for the Montreal Home Guard during World War I.

A 1979 Savage Arms catalogue claimed that in 1919, Arthur Savage was approached by Chief Lame Deer to buy rifles for his tribe in New York. Lame Deer offered to allow Savage to use his image as its logo in exchange for discounted rifles and an annual fee. As of 2018, Savage Arms was still paying the annual fee.^[6] However, the Savage Model 1907 already bore the logo (including those made prior to 1919), and a catalog from 1903 shows Savage Arms using a similar illustration as well.

In 1920, Savage bought Stevens Arms of Chicopee, Massachusetts. In July 1921, a mortgage securing five promissory notes, each for $21,416, was filed in the County Clerk's office in Utica showing that the Savage Arms Corporation had purchased a "number of buildings erected by the government" during World War I for increasing the output of Lewis machine guns at the plant. The buildings included two large four-story brick structures, five large storage sheds, and one office building, a concrete mill building, steel storage building, power extension plant, shooting gallery and steel water tank with a capacity of 100,000 gallons. The notes were due in 1927. In 1929 Savage acquired the A.H. Fox Gun company of Philadelphia and moved production to Utica.

In 1939, Savage introduced the Model 24 combination gun (a configuration uncommon in the U.S.), which sold over a million copies. Savage was one of the few American makers of affordable double-barrel shotguns including the Fox Sterlingworth, Fox Model B, and Stevens Model 311 and produced rifles and shotguns under house brand names for large store chains.

Second World War

During World War II, Savage turned again to military production, making heavy munitions. Savage made most of the Thompson submachine guns used in World War II. Savage also produced the British No. 4 Lee–Enfield bolt-action rifle; though marked "U.S. PROPERTY," these rifles were never used by the US military and were instead sent to Britain under the Lend-Lease program. As quality wood was reserved for military gun stock production, Savage produced some Model 24 .22/.410 combo guns and Model 94 single barrel shotguns with stocks molded from Tenite plastic.

Post-war

After the war, it produced the model 67 and model 69 pump shotguns, including the model 69N stainless steel tactical pump shotgun. A variety of owners ran the company from the 1960s to the 1980s. Savage eventually ran into financial trouble in 1988 and filed for bankruptcy protection.

In addition to firearms, Savage Arms Corporation also sold power lawn mowers during this period.