Can modern-style plate carriers with plates be viably mass produced in the 17th-19th century? Just trying out some worldbuilding.
Having line infantry be able to take a musket ball to the largest exposed area and still be able to fire back sounds useful. I know 'bulletproof' cuirasses were made back then, but they are expensive; I'm imagining something for the common foot soldier, one single simple mass-produced plate that will be strapped to the front of your torso
Steel may work, but can isekai'd modern-day metallurgical knowledge be useable with their infrastructure? I imagine a viable thickness would be too heavy. Lead spalling can be taken care of by a layer of leather.
Ceramic backed by a textile composite might work too, to break the ball and then catch it, but silk is the only fabric I can think of has historical ballistics use and it's expensive. And can modern-day ceramics knowledge be useable back then too?