The Grizzly pistol was developed during the early 1980s by L.A.R. Manufacturing Inc USA (L.A.R. stands for names of company founders - Larisch, Augat and Robison). This pistol was designed around the very powerful .45 Winchester Magnum. Standard Grizzly Mark I pistols were sold chambered in .45 Win Mag, but patented factory conversion kits were available for additional calibers, including .45 ACP, 10mm Auto, .357 Magnum, and several others. Later on, LAR manufacturing also introduced two slightly enlarged versions of the Grizzly, known as Mark IV and Mark V. Mark IV pistols were chambered for the popular .44 Magnum revolver cartridge; the Mark V was chambered for very powerful .50AE ammunition. Although the manufacture of Grizzly pistols stopped in 1998, L.A.R. Manufacturing Inc is still in business and still offers spare parts on a very limited basis for Grizzly pistols.