Sven
Senior Member
How do bullets fly?
Quote:
A quite simple experimental photographic technique which enables the visualization of the flow of air in the vicinity of a moving body produces a picture called a "shadowgraph".
This technique requires a short duration flash of light, which must originate from a point. As shown in the figure , not even a photographic lens is required. The shadowgraph of the bullet, passing at very close distance in front of a film or photographic plate, visualizes the pressure differences of the flowfield particularly well.
The pictures shown in the three following figures were taken by applying this simple but effective technique.
A .308 Winchester (7.62 x 51 Nato) FMJ bullet traveling at approximately 2800 ft/s (850 m/s). Note the change in flow type from laminar to turbulent at the bullet´s cannelure.
A cal. .32 ACP (7.65 mm Browning) pistol bullet, moving at a speed considerably below the speed of sound. Only turbulences (the wake) can be observed behind the bullet´s base.
Source: How do bullets fly? - Author: Ruprecht Nennstiel, Pfingstbornstr.33, D 65207 Wiesbaden, German - check it out!
Quote:
A quite simple experimental photographic technique which enables the visualization of the flow of air in the vicinity of a moving body produces a picture called a "shadowgraph".
This technique requires a short duration flash of light, which must originate from a point. As shown in the figure , not even a photographic lens is required. The shadowgraph of the bullet, passing at very close distance in front of a film or photographic plate, visualizes the pressure differences of the flowfield particularly well.
The pictures shown in the three following figures were taken by applying this simple but effective technique.
A .308 Winchester (7.62 x 51 Nato) FMJ bullet traveling at approximately 2800 ft/s (850 m/s). Note the change in flow type from laminar to turbulent at the bullet´s cannelure.
A cal. .32 ACP (7.65 mm Browning) pistol bullet, moving at a speed considerably below the speed of sound. Only turbulences (the wake) can be observed behind the bullet´s base.
Source: How do bullets fly? - Author: Ruprecht Nennstiel, Pfingstbornstr.33, D 65207 Wiesbaden, German - check it out!
