Moar Doug Mills
(media.greatawakening.win)
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You are close to right about the velocity of the bullet (.223), it's maybe a little UNDER 3,000fps, but you're speaking of muzzle velocity, the speed at which the bullet comes out of the muzzle. Any bullet immediately begins doing two things... dropping AND losing velocity. You have to account for its travel 130 yards (or some say 150 yards) and realize that at that point, it is probably traveling around 2,000fps or perhaps less if encountering a headwind.
Muzzle velocity is always greater than terminal velocity.
Agreed. Muzzle velocities vary depending on loadings; I was grabbing a representative speed. But the mismatch still applies to 2,000 fps. At that speed, the bullet smear should have been only 6 inches long at a 1/8,000th exposure.
The bullet traveling slower would result in the smear being shorter, not longer… you said it should be 4.5 inches long at 3,000 ft/s, then said it would be 6 inches long at 2,000 ft/s.
Maff.
Well, that's what I said. I was mentally comparing it to the image that was taken. The problem, as I said at the outset, was that the camera speed and the bullet speed are not in synch, if the streak is taken to be the bullet
At 3,000 fps, and 1/8000th sec exposure, a streak would be 4.5 inches. At 2,000 fps, and 1/8000th sec exposure, a streak would be 3 inches.
According to this camera the 3000 fps assumption gives a 12-inch streak, so a 2000 fps assumption would correspond to an 8-inch streak.
Thanks for the catch. My apology and embarrassment. But it makes my point nonetheless.
You may also need to allow for air turbulence to the rear of the bullet, which can cause light distortion. Just thinking of all the possibilities.
It happens, but you need special equipment to see it (Schlieren or shadowgraph images). And you have to get up close and personal, so it is studied at shooting ranges. Reflective material (moisture) would show up regardless of any aerodynamics, and would not be seen as from any other location.
I've SEEN Shockwave following explosions and particularly trailing a .50 cal bullet. Humid air can create a sort of vapor trail and you can see it through a spotter scope.
Bottom line, there are a LOT of variables to any bullet trajectory, so I'm coming down on the side that the photo is legit.
IMHO, of course.