While the cartridges themselves are manufactured by Winchester, the design and technology involved is all Browning. Right now, Browning centerfire rifle ammo comes in .243, .270, .30/06, .30/30, .308, .300 Win Mag, and .300 WSM. Rather than bombard customers with a plethora of bullet weights and types, Browning has taken the simple route. For each cartridge (with the exception of the .243 and .30/30) there are two bullet weights and two bullet types. In the .30/06, for example, there is a 155-grain BXR (rapid expander) and a 185-grain BXC (controlled expander). The .243 and .30/30 have only a rapid-expanding loading.