Ah, the old crossbow—tension, the rack, the cock. Back in the 12th century they hammered iron into a bow that could hold 30,000 newtons, and they calibrated the lockwork to a fraction of a degree. That’s a precision you’d think only a modern bolt‑action could match, yet the .308 uses a bolt and a gas piston, all in an entirely different geometry. The crossbow’s power is stored in the wooden limbs, then released in a single motion; the .308 stores energy in a spring‑loaded bolt and relies on the chamber pressure to push it out. Both systems are elegant in their own way, but the crossbow’s designers had to account for material fatigue and uneven limb wear, things we only simulate now with finite element analysis. And yet, the modern rifle is built for repeatable accuracy across a range of temperatures and humidity—a variable the medieval engineer would have found nearly impossible to predict. So yes, the engineering has evolved, but the underlying challenge of converting stored energy into a predictable trajectory has been the same since the first war bows were forged.