Shooting on the moon, does

A

alinwa

oft dis'd member
Shooting on the moon does the bullet nose over?

I was just reading one of our resident ballisticians' explanation of the bullet nosing over (on another forum) and he characterized it by saying the bullet's nosing over is a "function of gravity."

I can't get with this........

IMO the bullet nosing over is an atmospheric phenomenon. Without atmospheric drag, no nose-over....

Any wintertime comments left? Anybody want to explore this? Or are we all 'zuberating in spring weather, planning on shooting instead of talking...??? (snowing like a mother here.... not windflag snow nuther....)

al
 
wow BR on the moon now how many benches they got there.I guess you dont need flags there.LOL.hurry up Scotty
 
alinwa said:
Shooting on the moon does the bullet nose over?


al
Click to expand...

Al,

I am glad you asked. It is quite a coincidence that I was considering who I could explain this pressing problem to. :)

When finally the bullet is pulled back to the moon by the forces of Lunar gravity it will be in perfect alignment as it was when it left the barrel and the terminal velocity will be the same as the muzzle velocity due to the total lack of atmosphere.

There now, Go out and play in the snow.

Professor Concho Bill
 
I can't afford the travel expense right now so this is just in anticipation of the cost reduction arc intersecting my life expectancy (how's that for optimism?). What is the escape velocity for a bullet in the moon's gravity? Can I get there (in the moon's thin atmosphere) with a BR or will I need a Dasher? What twist is best in VLA (very low atmosphere)? If I find my high tune node at exactly the orbital velocity in the moon's gravity, how much time will I have to clear my bench before my bullets circumnavigate and smack me in the back of the head? Will we need 600 yd moving backers to settle controversy about which pass of an orbital bullet made which hole? Will magnetic bag sand improve rifle tracking in moon gravity? Can a bullet back down a solar wind? Do these questions belong on that other board?
 
Last edited by a moderator:
A bullet nosing over would be dependant upon aerodynamic center of pressure, center of gravity of the projectile, and gyroscopic stabilization which fights axis movement. Without gravity you would have no axis movement in a neutral atmospheric condition until spin ran out, since forces would be balanced around the projectile in the forward axis. It would only slow, not veer. Technically, if the atmosphere was of perfect consistency, and the projectile was perfectly symmetric, the bullet would travel straight without needing spin.

On the moon, without atmosphere there is only center of gravity working on the projectile, but since there is no drag against the body, all mass would receive the same pull toward the surface, and the bullet would fall flat.
 
Last edited:
I used to notice this phenomenon in pistol matches with a .38 special. We called it keyholing. LOL :)
Long winter
Centerfire
 
Lunar Atmosphere = 100 Trillionth Earths, Lunar Gravity = 16.5% Earths. Hey I actually used a SEARCH.... Now if there was a Ballistic Program we'd be in business.... WOOHOO
 
Actually no Keith, IMO Bill nailed it down. Gravity would still bring it to moon quickly enough that the (1/1,000,000,000,000th??) atmospheric pressure wouldn't have time to mean much. "Lost in the regolith" as it were.

but of course I could be wrong :)

lol

al

We ARE getting some milage out of this after all!!

cool
 
It's funny how discussions like this point out the need for precision in communication..... (Keith started it!!) .... typical communication is so imprecise!

"escape velocity"....... the speed required for an object to leave the surface of whatever it's stuck to..... ISN'T A VELOCITY! Velocity is speed coupled with direction. "Escape velocity" is speed dependent, no direction specified. Escape velocity can be fairly rigorously defined though by reference to the object of origination. EXCEPT that this definition is also imprecise in that escape velocity varies from point-to-point on any given body for several reasons.

Whereas "launch velocity," another term commonly used to describe the speed required for an object to leave a gravity well is doubly vague. Number one it's not a velocity and number two a cricket has "launch velocity." It ain't gonna' clear the well but it has a launch speed. :)

Which brings me to my point, Keith makes a real and valid point about the bullet nosing over on the moon. The moon DOES have an atmosphere do the bullet DOES nose over some!!! (((( May I drag in the story about "would you sleep with me for a dollar? How about a hundred dollars? A MILLION???"))))

Point is it's relative... my original question really should have been "is nosing over a GRAVITY function or a DRAG function" but it wasn't, I blew it a little.

So thank you Keith for your correction, I guess we'd have to move into 6DOF interstellar ballistics to really get to flight unaffected by atmospheric influence but I have to agree that his point stands, muddled metaphors to the contrary notwithstanding.

So I guess Keith ended it too!

Let The Definitive Answer Be Keith's

I stand corrected

LOL

al
 
mks said:
Escape velocity is on the website I linked: 2.38 km/s = 7808 fps
Click to expand...

I linked to the same web site and arrived at the same answer.

Next question: What is the maximum distance that a bullet can travel on the moon if it has a muzzle velocity of 4100 feet per second?

An easier question is how high can the same bullet go if shot directly up from the surface of the moon?

Professor Concho Bill
 
You must log in or register to reply here.
Back
Top