Let You Do Scientific Research, and You Develop Steel Armor?

Once across the Celestial Empire, Gu Xian joined the Security Bureau and was responsible for the research, development and transformation of various firearms. Mission One: Develop a high-power portable pistol Bang! One shot and the tank was destroyed. Is this a pistol? ! Task 2: Research sniper rifles. Wait, this caliber is larger than a tank barrel. You call this a sniper rifle? ! A single shot, with a scope, and one shot in seconds, it is a sniper. Task 3: Research portable body armor. "Holy crap! This is a body armor, this is a steel armor, right?!" Under Gu Xian's leadership, China's technology tree lit up at an astonishing speed. Wait, maybe the Nantianmen Project can be restarted...