The best BS you've ever heard at the gun counter

[BamBams]

Gun shops do seem to attract a very diverse crowd of people!  I enjoyed them all.  The crack pots really helped me to pass the time. With one exception though:  It's the husband who buys the revolver with the 15 pound trigger pull for his petite wife and expects her to use it, ONCE, when somebody breaks into the house.

Oh yeah, I quit my job at gun shop back in July.  The owner wanted me to work my tail off, but didn't want to pay me on time -- if at all.

[whodowl]

He's going to bring me proof that he is correct, on Monday.

Well, it be Monday, remark Dali Llama...

Technically, Shorty's friend is correct.  At approximately 26,400fps the fired bullet defies gravity and enters orbit.  Also, at some distance (dependent on bullet ballistics) the fired bullet will breach the earth's curvature relative to trajectory and must then fall a greater distance than that of the dropped bullet.  In both cases the dropped bullet reaches "ground zero" first.

Practically, 26,400fps is impractical.

It do be Monday, indeed.

[Dali Llama]

I quit my job at gun shop back in July.  The owner wanted me to work my tail off, but didn't want to pay me on time -- if at all.

Do not that typically be the case, inquire Dali Llama?  What do BamBams be doing now, ask Dali?

[powderman]

WHODOWL. Not really. All ya need is a case extender, another handfull of powder, and them boattail bullets. Not safe with regular bullets, only those new fancy boattail bullets,  they just naturally float up because of their unique design.  :-D  :-D  :-D  :-D Uhhhh, by the way, I live in KY. Charlie, aka POWDERMAN.    

[SAWgunner]

Yep...a little over 17000 mph to maintain an orbit.  We come into a couple of problems here, though.  The fastest burning pyro I have dealt with would be some 20k fps det-chord (probably not good on barrels).  I know that rail guns can achieve insane levels of speed.  Just not possible (but I bet that rail gun in a flat shooter.).  In dealing with the rail gun, the guy said that they are so hard to develop because the rails have to be able to withstand alot (read as more than you non-electricians have ever seen) of current, extreme heat, and have to be inhumanly perfect as far as tolerances go.  He mentioned that the projectiles have a habit of arc-welding to the rails if everything is not kosher.  Oh yeah, then there is the problem of machining your own "perfect" projectiles.  Not a very practical weapon, which is why I guess "they' are pursuing other weapons systems.  Laser weapon systems come to mind.





Technically, Shorty's friend is correct.  At approximately 26,400fps the fired bullet defies gravity and enters orbit.  Also, at some distance (dependent on bullet ballistics) the fired bullet will breach the earth's curvature relative to trajectory and must then fall a greater distance than that of the dropped bullet.  In both cases the dropped bullet reaches "ground zero" first.

Practically, 26,400fps is impractical.

It do be Monday, indeed. [/quote]

[Shorty]

OK, guys, I got the PROOF, but from another member of our brain trust.
This "theory" of gravity is giving me grief at work.  I'm stupid AND stuborn!   :shock:
First, some simple prelim's. as advocated;
A; A speeding bullet overcomes the force of gravity because it has so much more energy than gravity.  That's called "momentum".  Gravity being so weak that picking up ones foot requires little effort.
B; Even the dropped bullet, although it starts at zero acceleration, DWELLS for a millisec. before beginning to drop.  Thats called "inertia".  
 
Now for the example give; An actual US Army proving grounds test;
Shooting a rifle at zero elevation, 5 feet above ground, 123 Gr. bullet at 2329 ft/sec ( this is relevant because the mass and speed determines its ability to defy gravity).  The bullet dropped 26 1/2 inches at 700 yds. and took 1.6 sec's to get there.  I don't know if that makes sense.
OK, the dropped bullet fell 5 ft. at 32 ft/sec/sec and took .166 sec's to hit the ground.  Therefore the bullet in flight stayed "up" longer.

Please, somebody give me a authoritative reference to the "bullet drop" test of the law of gravity, or is it just theory.  

[whodowl]

WHODOWL. Not really. All ya need is a case extender, another handfull of powder, and them boattail bullets. Not safe with regular bullets, only those new fancy boattail bullets,  they just naturally float up because of their unique design.  :-D  :-D  :-D  :-D Uhhhh, by the way, I live in KY. Charlie, aka POWDERMAN.    

 Hey POWDERMAN   Beuatiful state, Kentucky.  Love those hills and hollers ya got there, particularly the eastern part.  My mother and her folks were originally from the Munfordsville area. Dave aka Whodowl  

[Nightrain52]

MY HEAD HURTS. :-D      :-D    :-D    

[naedlaen]

Shorty wrote

OK, the dropped bullet fell 5 ft. at 32 ft/sec/sec and took .166 sec's to hit the ground. Therefore the bullet in flight stayed "up" longer

The formula is x=v*t+0.5*a*t*t
  x= distance, feet
  v=velocity f/s
  t= time, s
  a= acceleration f/s/s

Dropping an object that has negligible air resistance 5 feet will take about 0.557 seconds.

Shorty wrote

Now for the example give; An actual US Army proving grounds test;
Shooting a rifle at zero elevation, 5 feet above ground, 123 Gr. bullet at 2329 ft/sec ( this is relevant because the mass and speed determines its ability to defy gravity). The bullet dropped 26 1/2 inches at 700 yds. and took 1.6 sec's to get there. I don't know if that makes sense.

I'll buy that it takes 1.6 seconds to travel 700 yards when it starts at 2329 fps.  I am not sure that I buy that it started at zero elevation, and therefore zero vertical velocity.  

A 223 Remington that is zeroed at 200 yards drops 26.5" (+/-) below the line of sight at 400 yards.  Since it has vertical velocity, gravity must overcome this velocity before the bullet starts to fall.  If an object has zero vertical velocity it will generally fall 16 feet in the first second.   If it falls for 1.6 seconds it falls about 41 feet.   (Neglecting air resistance)

An airplane resists gravity due to the lift created by the wing's shape.  The air has to travel a longer distance on top of the wing than the air below the wing.  This creates a low pressure area above the wing, allowing the higher pressure below the wing to lift the plane.  A plane's wing is not symmetrical.  A bullet is along its axis.  Therefore, I do not think that the bullet's movement through the  air movement creates a vast pressure difference like an airplane wing.

If you would provide more details about the Army test, I'd like to explore it further.    Maybe there really is a bullet that creates a low pressure area only on the top side of the bullet.

Neal

[Dali Llama]

I live in KY. Charlie, aka POWDERMAN.

 Hey POWDERMAN    Beuatiful state, Kentucky.  Love those hills and hollers ya got there, particularly the eastern part.  

Dali Llama say he like Bardstown area and its products. :grin:  :grin:  :grin:

[unspellable]

Just throw a log on the fire, stir the pot, and split the cat's whisker three ways, I'll chime in.

In a vacuum over a flat surface with a non-curved gravity field (The thought experiment type thing where you do away with all the complications.) a bullet fired on the level will hit the ground at the same time as one fired from the muzzle.

Now for the complications.

The Earth is more or less a sphere, so if there were no gravity or air, a bullet fired on the level and in a straight line will be rising with respect to the surface even though it is still on a straight line.  The straight line does not follow the curvature of the earth.  So in air the drop will be retarded a bit.  This effect would be far too small to measure.

A larger effect is the retardation of drop due to areodynamic lift.  If you do a close study of airflow around a bullet (It gets a bit complicated.) you will find there is a small amount of lift, considerably less than the bullet weighs.  An air foil does not have to be assymetrical.  Some areobatic airplanes have wings with symetrical upper and lower surfaces.  It is the areodynamic lift that probably accounts for the experiment above in which the released bullet dropped further than the fired bullet.  This effect does NOT produce any rise in the bullet's path it merely slows the drop.  That's due to the normal rifle being sighted so as to launch the bullet slightly upwards to compensate for the drop.

There is also a lateral drift caused by the Earth's rotation.  This effect is large enough that it is taken into account when aiming long range artillery.

[Shorty]

naedlaen,
You see my problem.  My coworker has used bogus "givens" from what he believes is a factual Army test to "prove" his pre-conceived results.  How does one argue with that?  :?
I guess that I need to find a high school physics text that gives that example of the law of gravity.  :roll:

[powderman]

Only a 26 inch drop at 700 yds cannot be correct, must have been a misprint. It would be much more of a drop than that. POWDERMAN.        

[naedlaen]

Hey Shorty,

I'll save you the trouble of finding a text book that discusses gravity.

I looked at Winchesters ballistic table last night.  The 123 grain bullet travelling at 2360 (+/-) is the 7.62x39.  And sighted in at 200 yards it drops 48" (+/-) at 400 yards with a soft point.   The FMJ probably maintains velocity better, but at 700 yards the drop has got to be more than 26".

By the way, if you average the velocities every 100 yards out to 400 yards, it takes about 0.7 seconds for the bullet to travel the 400 yards.  At 400 yards it is 46" below the sight line.  Adjusting to a level barrel, it is not too much of a jump to see that there could be an additional 12" of drop to 5' total; the same drop in about the same time as a bullet dropped vertically with no forward motion. (winchester.com has ballistics for 7.62x39 Russian soft point)

And I am glad that you read my first post as I intended.  As I was looking at the ballistic table last night I realized that you were repeating the proof that was offered to you, and I had not addresses that in my post.

unspellable- yes, it looks like there may be a small lift force on the bullet in this case, but not like shorty's aquaintance would have us believe.
Neal

eidts in italics

[Shorty]

naedlaen,
You're right, of course.  Today my "friend" admitted that he thought a rifle barrel was "level" when sighted in to 400 yds!  :roll:
I had to diagram what happens when one elevates the rear sight to make the barrel UNLEVEL!   I think that he finally "got it".  

[Dali Llama]

Today my "friend" admitted that he thought a rifle barrel was "level" when sighted in to 400 yds!  

:lol:  :lol:  :lol: