knew that the rifling was a meticulously crafted process.Otherwise, the gun prototypes that existed in Ming and early Qing dynasties would not have remained underdeveloped for so long. One major hurdl...
knew that the rifling was a meticulously crafted process.Otherwise, the gun prototypes that existed in Ming and early Qing dynasties would not have remained underdeveloped for so long. One major hurdl...