Thread: Accuracy at 100 vs 600 (example). Variations in accuracy at different ranges

Originally Posted by vulcannz

What second sound barrier?

I believe he's referring to the fact that a bullet, once sent on its way will break the sound barrier somewhere along the length of the barrel whilst being accelerated by expanding propellant gases, then as drag from the atmosphere slows the projectile down, somewhere down range the projectile will pass back through the sound barrier a second time.