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Shooting at the courthouse

Started by Nik, March 07, 2012, 02:45:30 PM

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patric

Imagine what this could have been like if it wasn't some depressed person looking to be taken out.
If he had intended to do some real damage, he might have brought more than five bullets in a revolver.
"Tulsa will lay off police and firemen before we will cut back on unnecessarily wasteful streetlights."  -- March 18, 2009 TulsaNow Forum

Gaspar

Quote from: patric on March 12, 2012, 01:59:25 PM
Imagine what this could have been like if it wasn't some depressed person looking to be taken out.
If he had intended to do some real damage, he might have brought more than five bullets in a revolver.

I doubt it.
When attacked by a mob of clowns, always go for the juggler.

jacobi

QuoteIf the bullet was not fired straight up, gravity would not exercise as much force on depleting the energy of the projectile, and it could travel much faster.

One of the things discussed on that mythbusters ep was that the cases where people have been hurt are usually from people firing up, but at an angle.  With the distances traveled by bullets, it doesn't take much of a move of the hand when firing to make a huge difference in the skew of the vector at the hieght of the bullet's trajectory relative to the position of the shooter.  I wonder what the min nec. angle of fire would be to get the bullet to arch over rather than just expend its force and return at terminal velocity only.  TO THE LAB!
ἐγώ ἐλεεινότερος πάντων ἀνθρώπων εἰμί

heironymouspasparagus

Quote from: Townsend on March 12, 2012, 11:27:00 AM
A five ounce bird could not carry a one pound coconut.



Use a bumblebee then...
"So he brandished a gun, never shot anyone or anything right?"  --TeeDub, 17 Feb 2018.

I don't share my thoughts because I think it will change the minds of people who think differently.  I share my thoughts to show the people who already think like me that they are not alone.

heironymouspasparagus

Quote from: jacobi on March 14, 2012, 06:36:54 AM
One of the things discussed on that mythbusters ep was that the cases where people have been hurt are usually from people firing up, but at an angle.  With the distances traveled by bullets, it doesn't take much of a move of the hand when firing to make a huge difference in the skew of the vector at the hieght of the bullet's trajectory relative to the position of the shooter.  I wonder what the min nec. angle of fire would be to get the bullet to arch over rather than just expend its force and return at terminal velocity only.  TO THE LAB!

There is a distance/velocity curve to every bullet, related to what Gaspar said about terminal velocity.  45 degrees is the angle for the intersection of distance traveled versus velocity.  Below 45, the velocity is higher (but declining) while the distance is shorter, but increasing.  Above 45, velocity is lower (and still declining) while distance is shorter and declining.

"So he brandished a gun, never shot anyone or anything right?"  --TeeDub, 17 Feb 2018.

I don't share my thoughts because I think it will change the minds of people who think differently.  I share my thoughts to show the people who already think like me that they are not alone.

jacobi

QuoteThere is a distance/velocity curve to every bullet, related to what Gaspar said about terminal velocity.  45 degrees is the angle for the intersection of distance traveled versus velocity.  Below 45, the velocity is higher (but declining) while the distance is shorter, but increasing.  Above 45, velocity is lower (and still declining) while distance is shorter and declining.

I guess i'm wondering at what point the bullet loses it's rifling spin, becomes less stable and thereby hemorages momentum.  BTW, you guys inspired me, I'm watching mythbusters now.
ἐγώ ἐλεεινότερος πάντων ἀνθρώπων εἰμί

Townsend


Gaspar

Quote from: jacobi on March 14, 2012, 08:03:23 AM
I guess i'm wondering at what point the bullet loses it's rifling spin, becomes less stable and thereby hemorages momentum.  BTW, you guys inspired me, I'm watching mythbusters now.


That's extremely dependent on the round, and the gun.  The gun this shooter was using was a S&W Centennial.  It holds 5 rounds either .38 or .357.  It only has about a 3" barrel.  This produces a very unstable rifle spin, and unpredictable ballistic path.  Because it is a short barrel revolver, gas also escapes around the firing chamber, therefore the barrel does not serve as an expansion mechanism for gasses.  This gun is designed for close encounters.  A longer barrel will produce more friction, but also a more stable spin, and if the firing chamber and barrel are one (semi-auto pistols, rifles) the barrel offers a smooth expansion chamber for the round's gasses. This gives you more distance, more stable spin, and more accuracy.

Different manufactures and products also offer different twist ratios.  An AK-47 may have a twist of 1:8, that means the bullet makes one complete rotation every 8 inches.  Some may be as low as 1:12.  Some graduate from almost no twist to a tight 1:8 by the end of the barrel.  Each dictates a different muzzle velocity and stability characteristics.  

When attacked by a mob of clowns, always go for the juggler.

heironymouspasparagus

Quote from: Gaspar on March 14, 2012, 09:22:07 AM
That's extremely dependent on the round, and the gun.  The gun this shooter was using was a S&W Centennial.  It holds 5 rounds either .38 or .357.  It only has about a 3" barrel.  This produces a very unstable rifle spin, and unpredictable ballistic path.  Because it is a short barrel revolver, gas also escapes around the firing chamber, therefore the barrel does not serve as an expansion mechanism for gasses.  This gun is designed for close encounters.  A longer barrel will produce more friction, but also a more stable spin, and if the firing chamber and barrel are one (semi-auto pistols, rifles) the barrel offers a smooth expansion chamber for the round's gasses. This gives you more distance, more stable spin, and more accuracy.

Different manufactures and products also offer different twist ratios.  An AK-47 may have a twist of 1:8, that means the bullet makes one complete rotation every 8 inches.  Some may be as low as 1:12.  Some graduate from almost no twist to a tight 1:8 by the end of the barrel.  Each dictates a different muzzle velocity and stability characteristics.  



Good for about 20 feet (3" barrel) if you are lucky.  I have acquaintances who talk about their hunting prowess with a .357 revolver with 6" barrel (Colt, Smith, or Ruger, depending on the "liar") and how they are able to take down a running deer at 100 yards!

There is some expansion in the barrel, but most leaks out the cylinder end.  All of the gas just can't get out at the end of the cylinder before pushing down the barrel, too.

Obviously have never shot a revolver at anything anywhere close to 100 yards.  Or seen a running deer at 100 yards.  Hitting anything smaller than about a one foot target at 100 yards is a crap shoot - fairly easy at a range, with no outside influences, like running deer, or trees, or the other distractions typically found in the field.  Hunting that way would be exceptionally irresponsible.






"So he brandished a gun, never shot anyone or anything right?"  --TeeDub, 17 Feb 2018.

I don't share my thoughts because I think it will change the minds of people who think differently.  I share my thoughts to show the people who already think like me that they are not alone.

patric

Quote from: jacobi on March 14, 2012, 06:36:54 AM
One of the things discussed on that mythbusters ep was that the cases where people have been hurt are usually from people firing up, but at an angle.  With the distances traveled by bullets, it doesn't take much of a move of the hand when firing to make a huge difference in the skew of the vector at the hieght of the bullet's trajectory relative to the position of the shooter.  I wonder what the min nec. angle of fire would be to get the bullet to arch over rather than just expend its force and return at terminal velocity only.  TO THE LAB!

So is someone trying to say the deputy who was shot in both hands/arms was hit by a bullet returning to earth?
"Tulsa will lay off police and firemen before we will cut back on unnecessarily wasteful streetlights."  -- March 18, 2009 TulsaNow Forum

BKDotCom

Quote from: patric on March 14, 2012, 12:26:34 PM
So is someone trying to say the deputy who was shot in both hands/arms was hit by a bullet returning to earth?

No.  Certainly no bullet that left the earths atmosphere.
We're just trying to determine how dangerous it is to fire a gun into the air.  Which is apparently all the suspect did.
If I deciphered Shadow's post correctly, I believe he was trying to say it's a first amendment thing.... that's just how people celebrate.
The law, common sense, and mythbusters say "don't do it".

nathanm

I believe the issue is illustrated quite clearly in this clip from Ronin:



If the forum doesn't pass through the time tag, go to 1:17.
"Labor is prior to and independent of capital. Capital is only the fruit of labor, and could never have existed if labor had not first existed. Labor is the superior of capital, and deserves much the higher consideration" --Abraham Lincoln

heironymouspasparagus

Quote from: BKDotCom on March 14, 2012, 01:11:26 PM
No.  Certainly no bullet that left the earths atmosphere.
We're just trying to determine how dangerous it is to fire a gun into the air.  Which is apparently all the suspect did.
If I deciphered Shadow's post correctly, I believe he was trying to say it's a first amendment thing.... that's just how people celebrate.
The law, common sense, and mythbusters say "don't do it".

No commercial ammunition will achieve escape velocity.  I don't believe the guy just shot up in the air.  While it is possible, the odds are just too huge to believe.  And the time interval would have been seconds before the deputy was shot rather than almost instantaneously.  One of the sequences of pictures showed the guy with the gun in the general direction of the deputy, then the next frame showed the deputy down, with another one shooting at the guy.  That was less than many seconds, it appeared. 

Any recent physics students that can do the math in their head?  .38 special from 2.5" barrel, about 1400 fps.  Straight up, the first second, about 1400 feet.  Second second ??  Speed reducing  32 fps/second.  Stops in a few seconds (3 or 4?).  Then must accelerate back down for a few more.  It looks like the whole thing was over by the time the bullet could get back down.


"So he brandished a gun, never shot anyone or anything right?"  --TeeDub, 17 Feb 2018.

I don't share my thoughts because I think it will change the minds of people who think differently.  I share my thoughts to show the people who already think like me that they are not alone.

patric

Quote from: heironymouspasparagus on March 14, 2012, 07:05:27 PM
One of the sequences of pictures showed the guy with the gun in the general direction of the deputy, then the next frame showed the deputy down, with another one shooting at the guy.  That was less than many seconds, it appeared.

Unless all the sources are wrong, the deputy nearest the north courthouse doors (and surveillance camera) crouching in the published photos is not the same as the one that was wounded.
I thought the same thing at first glance myself, but the photographer captioned the photo as the deputy ducking for cover.
"Tulsa will lay off police and firemen before we will cut back on unnecessarily wasteful streetlights."  -- March 18, 2009 TulsaNow Forum

Gaspar

Quote from: patric on March 15, 2012, 11:05:26 AM
Unless all the sources are wrong, the deputy nearest the north courthouse doors (and surveillance camera) crouching in the published photos is not the same as the one that was wounded.
I thought the same thing at first glance myself, but the photographer captioned the photo as the deputy ducking for cover.


Simple crossfire incident.  No need to over-analyze it.  Dealing with large bollards and round cement planters there is multiple opportunities for ricochet, and no way for an officer to know where that shot will wind up.  A solid round object can deflect a bullet or a fragment by as much as 45 degrees.
When attacked by a mob of clowns, always go for the juggler.