After playing around with various iterations of the 6.5mm in an intermediate case (akin to 6.5 grendel) I decided to take a look at potential 6mm rounds in the same size class.
The ide was to see what sort of hunting round could be developed around a small action rifle like the CZ-527. In addition, it would be handy of the round would fit in the AR-15. Here is the latest result, the 6x43mm CZ
The cartridge is based on the Czech 7.62x45mm, and used the same case head size as the 7.62x39. Cases can be formed from 7.62x45mm, 6.5 Mannlicher-Schoenauer or 6.5 Carcano. Opertaing pressure is 4300 bar, about 62,000 PSI, the same as the parent cartridge. Loaded to 90% pressure, this round will (per QuickLoad) drive a 100 gn Sierra SPBT at 2900 fps from a 24 inch barrel. By comparison, 243 will drive the same bullet at 3029 fps at the same 90% peak pressure.
The cartridge has a 20 degree taper, similar to 223 and 308, and the same 35 degree shoulder found on the short magnum catridges. No consideration was given to long, high BC match rounds. This cartridge was intended to be a light hunting round. In that role, it can come within 100-200 fps of the 243 with bullets weighing 100gns or less.
Since I designed this round with the CZ-527 as the most likely platform, I am tenatively calling this the 6x43mm or 6mm CZ.
Comments are welcome.
The ide was to see what sort of hunting round could be developed around a small action rifle like the CZ-527. In addition, it would be handy of the round would fit in the AR-15. Here is the latest result, the 6x43mm CZ
The cartridge is based on the Czech 7.62x45mm, and used the same case head size as the 7.62x39. Cases can be formed from 7.62x45mm, 6.5 Mannlicher-Schoenauer or 6.5 Carcano. Opertaing pressure is 4300 bar, about 62,000 PSI, the same as the parent cartridge. Loaded to 90% pressure, this round will (per QuickLoad) drive a 100 gn Sierra SPBT at 2900 fps from a 24 inch barrel. By comparison, 243 will drive the same bullet at 3029 fps at the same 90% peak pressure.
The cartridge has a 20 degree taper, similar to 223 and 308, and the same 35 degree shoulder found on the short magnum catridges. No consideration was given to long, high BC match rounds. This cartridge was intended to be a light hunting round. In that role, it can come within 100-200 fps of the 243 with bullets weighing 100gns or less.
Since I designed this round with the CZ-527 as the most likely platform, I am tenatively calling this the 6x43mm or 6mm CZ.
Comments are welcome.