The Mukden Arsenal Mauser also known as the Model 13 Mauser and Liao Type 13 was a rifle that implemented characteristics of both the Mauser Type 4 and the Arisaka rifles. They were mostly built in the Mukden arsenal in Manchukuo.
The symbol of Mukden arsenal
The 6.5×50mmSR Arisaka is a semi-rimmed rifle cartridge with a 6.705 mm diameter bullet. It was the standard Japanese military cartridge from 1897 until the late 1930s for service rifles and machine guns when it was gradually replaced by the 7.7×58mm Arisaka.
6.5×50mmSR Arisaka (center) with .303 British (left) and .30-06 (right).
Japanese military 6.5×50mmSR Arisaka round (Type 38)