Do heavier bullets drop faster than lighter bullets....

[misANTHrope]

Umm, Mis, horizontal velocity has literally NO effect on bullet drop, in essance because the bullet itself produces zero list capability. IF the bullet produced lift, then horizontal velocity and vertical velocity would be related, but since it does not, they are not.

In relation to TIME, all bullets fired exactly horizontal will drop at exactly the same speed (this is for modern bullets, not round-ball bullets which can actually produce lift-like aerodynamic properties)

Now, over distance, differant rounds/loads will drop at a differant rate per amount of feet traveled foward, this is simply due to the fact that one bullet may travel 1500 feet in 2 seconds, whereas another bullet only travels 1000 in 2 seconds, and yet a third will travel 2000 feet.

At the 2 second mark, all bullets have dropped the same, but at the 1,000 foot mark, their drops are differant, because for the fastest bullet, that is only 1 second into flight, for the slowest, that is 2 seconds, it will have dropped signifigantly further by that distance.

You've basically repeated what I was saying, except in perhaps a more coherent fashion. I think I tend to lose coherence the more I type.

 

[Snapping Twig]

I thought Newton settled this particular debate centuries ago.

Everything falls at the same rate for a given weight.

Pound of feathers, a pound of lead... both hit the ground at the same time.

 

[Happiness Is A Warm Gun]

Boomer (and others) got it right.

All objects are accelerated towards the earth at the same rate (9.8m/s2).

Take two bullets.
Load one into a rifle and hold the other in your hand.
Keep both bullets at equal height.
Aim gun level to horizon.
Pull trigger and drop bullet in your hand.
Both bullets will hit ground at EXACT same time.

Horizontal velocity doesn't affect vertical velocity, acceleration, or displacement.

Bullet size, or weight doesn't affect vertical velocity, acceleration, or displacement.

So what does this mean?

At any point in TIME any two bullets will have dropped the EXACT same distance (vertical displacement) regardless of their weight, size, or muzzle velocities.

Since two bullets with DIFFERENT muzzle velocities will travel different distances down range in any given amount of time (say 0.1 sec) they will be at different distances down range for the same amount of drop.

Likely what the OP is interested in is:
At a static distance (say 50meters) which bullet drops more.
The bullet with FASTER VELOCITY will get their quicker. Since acceleration downward towards the earth is a constant it will have less time to fall and thus fall less.
Faster Round = less drop
Slower Round = more drop

Generally heavier rounds have lower velocity so they will drop more but this is due to the velocity not the weight, shape, or caliber of the round. If you took two rounds say 115gr 9x19 and a 230gr 0.45 and modified the powder load so they had exact same muzzle velocity they would have similar drop.

To back this up here is some data on my favorite SD rounds.

9x19 Federal LE HST 124gr
Muzzle Velocity: 1150 fps
Range: 25 50 75 100
Drop: 0 -0.9 -3.8 -8.8

9x19 Federal LE HST 147gr
Muzzle Velocity: 1000 fps
Range: 25 50 75 100
Drop: 0 -1.4 -5.2 -11.5

.45ACP Federal LE HST 230gr
Muzzle Velocity: 890 fps
Range: 25 50 75 100
Drop: 0 -2.0 -6.9 -15.0

.45ACP +P Federal LE HST 230gr
Muzzle Velocity: 950 fps
Range: 25 50 75 100
Drop: 0 -1.6 -5.9 -12.8

Notice the heavier bullet 9x19 bullet drops more but this is due to it's lower velocity. Since it travels slower it will be affected by gravity longer for any given range (25, 50, 75 yards) and fall more.

Compare that to the 2 .45 rounds. The slower 45 drops more than the faster 45 even though they have same weight. The +P 45 drops very similar to the 147gr 9x19 because they have similar muzzle vel 950 vs 1000.

You lost me. What does all this mean?
Pure and simple: faster bullets drop less. Regardless of caliber or weight the rounds with higher muzzle velocity will drop less for any given distance. Remember: ALL objects accelerate downward at same rate BUT the faster bullet hits the target quicker so gravity has less time to pull the bullet downward thus it doesn't drop as much.

EDIT: Air resistance does come into play however the time frames involved (<0.1 sec) and the aerodynamic shape of bullets mean that air resistance will be extremely minimal. Small variations in round crimp, bullet weight, powder measure will all have a magnitude more impact than air resistance.

 

[jmr40]

There is no mystery here. The question has been answered for decades, but to answer the question you first have to define long range. I will use the 30-06 as an example. Many hunters use the 150 gr bullet because it leaves the muzzle faster, around 2900 fps. They argue that since it is moving faster than a 180 gr bullet at 2700fps it will shoot flatter. Out to around 500 yards this is true. The lighter bullet will have about 7" less drop. 42" vs 49", assuming a 200 yard zero for both rounds. I'm using Remingtons ballistic chart for reference, using the most efficient loadings listed.

The ballistic chart stops at 500 yards and many people asume this trend continues but it does not. While the lighter bullet started out 200fps faster it also slows down faster and at 500 yards there is only about a 50fps advantage. Somewhere after 500 yards the heavier bullet will pass the lighter one and have less drop.

It really does come down to velocity. The faster a bullet is moving, the faster it will reach the target and the less time gravity has to work on it. It is just that at really long ranges a heavier bullet will maintain velocity better and will drop less than a lighter bullet. Like I said earlier you first have to define long range.

 

[ranger335v]

Actually, neither weight nor shape nor forward velocity mean a thing to the question as it was stated.

Both the light and heavy bullet will "hit the ground" at the same time. One may be much further down range but the drop time will be the same if they are fired on identical paths and over a flat surface.

There it is, no math!

 

[Happiness Is A Warm Gun]

Actually, neither weight nor shape nor forward velocity mean a thing to the question as it was stated.

Both the light and heavy bullet will "hit the ground" at the same time. One may be much further down range but the drop time will be the same if they are fired on identical paths and over a flat surface.

There it is, no math!

The bullets will always hit ground at the same TIME but not at the same place.

So velocity does matter if shooting at a fixed distance say 100m (or any distance). The slower bullet will hit lower. Why? because although the two bullets will fall/drop at the samw rate, the slower one will take longer to arrive.

Thus fire two groups from benchrest at 100m target. One w/ high velocity and one w/ low velocity. The one with low velocity will hit lower.

The drop is always the same based on TIME but since distance is based on velocity the higher velocity will have lower drop at ANY DISTANCE.

Weight doesn't matter directly ONLY velocity. Of course most heavier loads are also slower but it is the actual speed of the bullet not it's weight that causes the higher drop.

 

[csmkersh]

Long ago Galileo proved that objects of different weights drop at the same speed.

It's not that heavier bullets drop faster, it's that their lateral speed is slower and they drop the same amount in a shorter distance.

:banghead:

​

 

[divemedic]

Actually, a lighter bullet would travel faster in the horizontal plane, assuming they were of the same caliber. This means, that due to the curvature of the Earth, the bullet which travels farther in the horizontal plane will have to fall a longer distance to hit the ground. Therefore, a faster bullet will hit the ground after a slower, heavier bullet due to the curvature of the Earth.

See, I can do it, too.

 

[yeti]

Actually, a lighter bullet would travel faster in the horizontal plane, assuming they were of the same caliber. This means, that due to the curvature of the Earth, the bullet which travels farther in the horizontal plane will have to fall a longer distance to hit the ground. Therefore, a faster bullet will hit the ground after a slower, heavier bullet due to the curvature of the Earth.

See, I can do it, too.

Assuming the earth is round.

 

[NCsmitty]

The practical side of this discussion is that if you take two bullets of the same weight, one a flat base and the other a boat tail, and start them at the same muzzle velocity, the boat tail will drop less shooting in a 1000 yard match. Plain and simple aerodynamics. It's all about the BC baby.

NCsmitty

 

[Seancass]

i thought the origional question stated SAME SPEED. not same load. theoretical, different mass, same speed.

i think some people here are applying 8th grade science to college level physics and calculus.

And we're trying to argue about different things. a bullet dropped or a bullet fired? are we on earth or in a vacuum? are these bullets going fast and measured to perfection or rocks dropped by Galileo measured with guestimations?

Projectiles traveling through a fluid do not behave in pretty algebraic fashions. Making it that simple is just wrong.

 

[kcshooter]

Both the light and heavy bullet will "hit the ground" at the same time. One may be much further down range but the drop time will be the same if they are fired on identical paths and over a flat surface.

Exactly. Bullet drop is a measure of distance, not time.

 

[Happiness Is A Warm Gun]

A lighter bullet doesn't automatically travel faster. The bullet muzzle velocity is based on the cartridge specs.

Some 0.45ACP +P 230gr have a higher velocity than a 147gr low recoil round.

The only thing that matters is VELOCITY of the round.
All objects fall at the same rate (i.e y axis acceleration is exactly same).


When shooting at a fixed target (1yard, 5 yards, 1000yards) the slower round will drop more. It is very simply due to the fact that the slower round takes longer to reach target therefore it is subject to gravity longer.

 

[NCsmitty]

I think if more people would apply practical ballistics and experience instead of trying to dazzle us with their prowess in "college level physics and calculus" theory, their proficiency at the range and in the field would possibly improve.
No one has addressed the hypothetical transition through transonic that may occur with one bullet weight and not the other, at least not at the same time. That may have an effect on the mathmatical outcome. We live in the real world where air resistance is different at subsonic compared to supersonic.

NCsmitty

 

[Seancass]

Exactly. Bullet drop is a measure of distance, not time.

Exactly. Acceleration has nothing to do with time.
wait....

dazzle us with their prowess in ... theroy

Theroy is easy, as shown by the calculations in this thread. It's reality thats complicated.

 

[whosyrdaddy]

IF the bullet produced lift, then horizontal velocity and vertical velocity would be related, but since it does not, they are not.

Not necessarily true. Given the relationship between the direction of spin and the direction of cross wind the bullet may indeed create lift. See Magnus effect.

 

[Cosmoline]

I thought how air resistance was a function of the BC, not the weight of the projectile. Thus you have excellent long range results with spitzer boattail rounds from the .50 BMG and even larger weapons.

 

[whyipackmy45]

No, they do not drop faster.

 

[Zak Smith]

The best way to determine what really happens (other than shooting) is to run one of the ballistic programs, set up the parameters of the gun and load, and try some different combinations.

You'll find that the combination of velocity and BC affect drop (as a function of distance).

If you want theory that works, pick up McCoy's magnum opus on external ballistics.

-z

 

[MaterDei]

Warning: My posts occasionally contain strong language (which may be unsuitable for children), unusual humor (which may be unsuitable for adults), and advanced mathematics (which may be unsuitable for liberal-arts majors).

You sig is very apropos.

 

[ronaldbeal]

fatal flaw

Without checking your math in detail ('cause I'm lazy!)
The first fatal flaw i see with your work is the incorrect assumption that "air resistance" is BV where B is a constant based solely on shape and air density. What you are describing is "drag coefficient"
Instead of drag coefficient, you need to use "ballistic coefficient"
Remember, an object at rest remains at rest unless acted upon by an outside force.
BC takes into consideration the inertial resistance that a greater mass will have for a given DC. Ultimately, the mass components of BC will cancel out. DC will have a small effect on the acceleration due to gravity, but the result will be the same for any DC given different masses.
Hope that helps
RB

 

[RPCVYemen]

Wait a second. Isn't the "air resistance" that would effect the speed with which the bullet drops the vertical air resistance?

In other words, the air is resisting the bullet's motion in two directions. One is in the horizontal direction - slowing the bullet's flight towards the target. The other is in the vertical direction - slowing the bullet's fall to the ground.

As I recall - and I am a soft headed liberal arts type - air resistance increased with the square of the velocity of the object through the air. Now the bullet's horizontal velocity is very high and slows the bullet down dramatically.

But the bullet's vertical velocity is pretty low (the same as if you held the bullet at the height of the muzzle and dropped it). At that low velocity, isn't the air resistance going to be negligible?

Mike

 

[CBS220]

Excepting differences in falling velocity due to small factors such as the weight of the bullet (affecting the vertical velocity, not the horizontal), two bullets will fall at the same speed. And the difference due to the shape of the bullets is going to be minute- I'm sitting here dropping a .323, a .454, a .224, and a .257 and they are all impacting the desk at the same time.

More velocity will allow a bullet to get farther before it smacks into the ground, however.

If you drop a bullet at the same time you launch an identical one from the barrel of a rifle, both will strike the ground at the same time.

 

[harmonic]

Guess I shoulda paid better attention in physics.

 

[ArmedBear]

I see a little silhouetto of a man,
Scaramouche,scaramouche will you do the fandango-
Thunderbolt and lightning-very very frightening me-
Galileo,galileo,
Galileo galileo
Galileo figaro-magnifico-