The 225 Winchester was introduced by Winchester in 1963 as a replacement for the 220 Swift. The timing was not ideal. Winchester's post-1964 shift immediately followed, and in 1965 Remington introduced the slightly faster 22-250. The 225 Winchester is, oddly, based on a rimmed case, but it is a fast and accurate cartridge with its 55-grain factory load developing 3570 feet per second. Only Winchester ever loaded the ammunition, and few other rifles were so chambered. -- Craig Boddington