Defensive Carry banner

1 - 20 of 35 Posts

·
Registered
Joined
·
70 Posts
Discussion Starter #1
Lets say you have a flat stretch of land. You take your 9mm handgun (any type) and holding level you fire it. How far would a target load ( no hot loads) travel before running out of steam before hitting the ground. I know bullet weight would make a difference. Just trying to get a close idea. Please don't guess . Wondering if anyone has had a real world knowledge.
 

·
Registered
Joined
·
1,208 Posts
Can't answer that but it wouldn't go very far if you pointed it level. If you want to get maximum distance, you'd have to point it upwards or it would hit the ground while it still had energy left.
So it could be one of two questions. How far will it travel if you point it level, or how far can it travel.
Can't answer either one though.
 

·
Super Moderator
Joined
·
19,238 Posts
How far the bullet will travel before it hits the ground is strictly a matter of how fast the bullet is going when it leaves the gun. That will be determined by the specific round fired and the ballistic coefficient (think "wind resistance") of the bullet.

So let's say it's a basic 115 grain FMJ round which has a characteristic muzzle velocity of 1180 ft/sec when fired from a 5" barrel. At this point, ballistics tables and calculators are probably every bit as good as "real world knowledge" because the terrain I shoot on will be different than yours. Hot day, cold day, humidity and altitude (barometric pressure) will all make a difference. So go here: Ballistic Calculator GunData.org and plug in your variables.

For the default values used for atmospheric conditions and a 25-yard zero (which assumes the bore is not exactly parallel to the ground), the bullet drop is about 56 inches at 200 yards. Thus if your muzzle is 56 inches above the ground and you are aiming carefully at a target at 25 yards, that bullet will hit the ground in 0.62 seconds. If your bore is higher off the ground, or is at a positive angle with respect to the ground, the distance covered will be longer.
 

·
Registered
Joined
·
121 Posts
Everything drops at the same rate regardless of weight. 16' per second per second. If you drop a bullet at the muzzle the same time as you fire a bullet, they will hit the ground at the same time. How far it goes is determined by the speed of the bullet (assuming a level shot). So if it leaves the muzzle at 1180 fps, one second later it will be 8' lower than the muzzle was held. The average velocity would be (muzzle speed + speed at one second)/2, which would also be how far it traveled in one second. So roughly, if you were holding the muzzle 4' from level ground the bullet would fly for 1/2 second, and if didn't loose speed it would have traveled 1180/2=590'. Of course it's going to slow down, so 590' is the max.
 

·
Registered
Joined
·
1,166 Posts
IRAQ8888 did a video on this on YouTube. There are two parts.
 

·
Registered
Joined
·
10,201 Posts
Acceleration from gravity is 32.17 ft/(sec^2). Distance traveled under constant acceleration is 0.5*(acceleration)*(time^2). If fired perfectly level at a height of six feet: 6 = 0.5*(32.17)*(time^2). So the time before it hits the ground is 0.6108 seconds.

If the average horizontal velocity is, say, 1100 ft/sec over that time, it would make it about 672 feet before striking the ground. (It could still travel further afterwards, of course.)
 

·
Registered
Joined
·
475 Posts
I remember doing these calculations in physics class in college. We did not take into consideration resistance due to air. Did enough of the problems then to make me realize I prefer others to do the math for me.

This post also made me think how I have more info available to me in my hand right now through my phone in my hand than my text books, and my phone also has more computing power than any computer I had available to me at the time.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
1,012 Posts
Lets say you have a flat stretch of land. You take your 9mm handgun (any type) and holding level you fire it. How far would a target load ( no hot loads) travel before running out of steam before hitting the ground. I know bullet weight would make a difference. Just trying to get a close idea. Please don't guess . Wondering if anyone has had a real world knowledge.
The idea that heavier objects will fall faster than lighter objects was debunked back in the 14th century by Galileo. So, no, bullet weight would not make a difference.
 

·
Premium Member
Joined
·
33,780 Posts
Being held level is what I'm after.
Held perfectly horizontal at eye level, my 9mm is about 67 inches off the ground. For a WWB 115 grain fmj, that puts it in the dirt at about 225 yards out. Still, it is moving at about 880 fps with about 200 f/p of energy remaining, so it is going to glance off the ground and continue its move downrange. When it will finally quit bouncing and come to a complete stop is anyone's guess.

Going at it another way, giving it the necessary holdover to remain airborne, at 1000 yards, its velocity has slowed to 500 fps with 64 f/p of energy. At 1500 yards, it has slowed to 370 fps with 35 f/p of energy remaining. At 2000 yards, it is moving at 324 fps with 27 f/p of energy remaining. ``
 

·
Registered
Joined
·
121 Posts
Acceleration from gravity is 32.17 ft/(sec^2). Distance traveled under constant acceleration is 0.5*(acceleration)*(time^2). If fired perfectly level at a height of six feet: 6 = 0.5*(32.17)*(time^2). So the time before it hits the ground is 0.6108 seconds.

If the average horizontal velocity is, say, 1100 ft/sec over that time, it would make it about 672 feet before striking the ground. (It could still travel further afterwards, of course.)
Yep, it's been 45 years since my last physics class and 15 years in retirement. I confused/mis-rememberd the gravity acceleration rate, because I used the shortcut-- things drop ~16 feet in the first second. Thanks for cleaning up my mess maxwell97.
 

·
Registered
Joined
·
4,105 Posts
The idea that heavier objects will fall faster than lighter objects was debunked back in the 14th century by Galileo. So, no, bullet weight would not make a difference.
Bullet weight won’t affect how fast a bullet falls vertically, but it can affect horizontal muzzle velocity and therefore affect how far each bullet will travel horizontally in the same amount of vertical drop time. 9 mm loads in 115, 124, and 147 gr often have different muzzle velocities. Would need to break out a ballistics calculator to show exactly what the difference is.
 

·
Registered
Joined
·
1,012 Posts
Bullet weight won’t affect how fast a bullet falls vertically, but it can affect horizontal muzzle velocity and therefore affect how far each bullet will travel horizontally in the same amount of vertical drop time. 9 mm loads in 115, 124, and 147 gr often have different muzzle velocities. Would need to break out a ballistics calculator to show exactly what the difference is.
Well, so does barrel length, amount of charge, etc. All other things being equal, bullet weight will not be a factor.
 

·
Registered
Joined
·
7,865 Posts
I’m just going to take a guess here...yes, you need a backstop behind where you’re shooting.
 

·
Registered
Joined
·
10,201 Posts
Yep, it's been 45 years since my last physics class and 15 years in retirement. I confused/mis-rememberd the gravity acceleration rate, because I used the shortcut-- things drop ~16 feet in the first second. Thanks for cleaning up my mess maxwell97.
No worries, you had the right concept. Constants are meant to be forgotten. :smile:
 

·
Registered
Joined
·
4,105 Posts
Well, so does barrel length, amount of charge, etc. All other things being equal, bullet weight will not be a factor.
Yes, you are right. If all else is equal, including ballistic coefficient, bullets at the same velocity will travel equally as far before hitting the ground regardless of weight.

However, in commercial target ammo 115 gr loads usually have a slightly flatter trajectory than 147 gr loads because their velocities are not equal.

Here’s a table from the ballistics calculator @gasmitty linked to, for American Eagle 115 and 147 gr loads. The difference is negligible out to 100 yards, but by 200 yards there’s a 4” difference in drop. Similar results will happen for most commercial loads out there. My understanding of the OP’s reference to bullet weight is he understands there will be this kind of slight variation.

 

·
Registered
Joined
·
3,280 Posts
Being held level is what I'm after.
t = sqrt of 2h/g h= ht above ground g = acceleration of gravity

Holding it level, it would take a little over half a second for the bullet to strike the ground. If the velocity was roughly 1000 ft/sec, that means it would travel a little over 500 ft.
 

·
Registered
Joined
·
249 Posts
Range depends on muzzle velocity and angle of elevation. The maximum range is achieved at 45 degrees elevation. More than 45, range drops proportionately, something we artillerists term "high angle" fire.
 
1 - 20 of 35 Posts
Top