On 2012-05-14, Existential Angst wrote:
"rob" wrote in message
. au...
"Ignoramus6213" wrote in message
...
I was at a gun range today with a friend, shooting a 9mm hand gun.
When he was shooting, I was standing behind him, watching. After a few
shots, I realized that I may have seen a glimpse of the bullets as
they flew downrange.
I watched some more, and it did seem this way, although it was hard to
see them and the barrel flash did not clarify things.
I am wondering, if, perhaps, it is known that flying bullets of that
sort of size and speed can be actually seen.
Depends on the background illumination -- but looking along the
flight path is probably the best bet for seeing one before the size
dwindles too small to be seen as it leaves your vicinity.
[ ... ]
I don't know & have never even fired a gun, however:
If you are standing close to directly behind the shooter your odds are
increased.
You can probably see a bullet out to 10 meters or so from behind. What is
the bullet's speed? How long would it take to travel the "visible" 10m?
1000 fps ~= 300m/s
T = 10/300 ~= 33mS
Not very long.
But very short times can seem longer in the excitement of the
moment. :-0
If you stand in the middle of the firing range, so that the bullet passes by
you at, say, 10-30 ft away, and you rotate yer head so that the angular
velocity subtended by yer eyes matches the angular velocity of the bullet
wrt to yer head, you have the best, uh, shot at actually seeing the bullet.
I believe you could, with some practice. Simple enough to do the calcs.
If 10-30 ft away requires an angular velocity/acceleration of the head/neck
that is muscularly unmanageable, this can be slowed by simply moving further
back (but still staying in the middle of the firing range), and mebbe with a
'scope or sumpn. You would also need a visual signal for when the trigger
is actually squeezed.
You need a varying angular rate, as the angle goes fastest when
the bullet is at right angles to you.
If you want to try this (and have plenty of steel between you
and *all* of the guns uprange :-) the best bet would be a small rotating
mirror triggered by the sound of the gun firing. Even with that, it is
rather tricky to control the angle rate to keep the bullet in view. A
spring driven one would be accelerating the whole time from release,
unless the spring is at neutral near the right angle point. Perhaps add
on a small flywheel to control the rate of acceleration and
deceleration.
But personally -- I would not want to be in that part of the
range, no matter how good the steel between me and the firing line was. :-)
Enjoy,
DoN.
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