6mm Remington International

Varmint Loads – and Then Some – for a Storied Cartridge.

- R.H. VanDenburg, Jr.

Perhaps no other cartridge has had the storied history of the 6mm Remington International. The story begins in 1915 with Charles Newton, who developed a .25-caliber cartridge for the Savage Model 99 rotary-magazine, lever-action rifle. The cartridge was introduced with an 87-grain bullet propelled to the then-amazing velocity of 3,000 fps. The company named the cartridge the .250-3000 Savage, and today it’s simply the .250 Savage, factory-loaded with a 100-grain bullet at 2,800 fps.

Almost immediately, experimenters began to explore the possibilities of the new case. It was, however, a full 20 years before the wildcat .22-250 showed up. In the mid-1930s, in California, then-Capt. Grosvenor Wotkyns and J.B. Sweaney necked the .250-3000 case to accept .22-caliber bullets. Wotkyns promoted the cartridge and contributed some ballistic ideas. Sweaney was the gunsmith and was assigned credit for the cartridge’s development. The early iteration of the Wotkyns-Sweaney .22-250 used barrels with groove diameters of .2225 to .2230 inch.

Farther east, Jerry Gebby of Dayton, Ohio, and J. Bushnell Smith of Middlebury, Vermont, together produced a similar cartridge. Gebby did the gunsmithing and Smith did the load development. Gebby christened the resulting product the .22 Varminter and copyrighted the name. In this case the pair used barrels with .224-inch groove diameters. The Wotkyns-Sweaney version went on to be referred to as the Wotkyns Original Swift, although Winchester, in introducing its .220 Swift in 1935, began with the 6mm Lee Navy case. The Gebby-Smith version is generally recognized as the predecessor to the current factory .22-250 cartridge. Interestingly, it was another 30 years (1965) before Remington formally announced the factory version, now called the .22-250 Remington.