Faster bullets at MV slower at distance

[ELR LVR]

Remember, the OP followed up and said the statement was about the same bullet, not two different bullets.

Wait what? I must have missed that
in the OP it did not allude to the same bullet
he stated his friend said "CERTAIN BULLETS" can slow down faster
If he followed up stating the same bullet then
---
the only way that can happen is if
1) he is borderline stable and the bullet looses stability after a certain range
2) the bullets are so crappy, their CG is off from center of form and they each fly different each having a different corrected BC in flight
---
When shooting the same bullet and conducting long range water line tests
if velocity starts out the same
they land at the same waterline
here is an example of such a test at 600 yds
they do the same at 1000, 1200, 1500, 2200
there will be some small vertical dispersion due to wind, heat, change in air density etc but
effectively the same if we neglect those things
I have a vid of doing this at 2200 yds, and aiming at the same spot, the bullet hits the same spot

 

[jelenko]

the OP it did not allude to the same bullet

Right. It was in a later post.
No big deal, just wanted to clarify for the OP that your answer wasn't contradicting other posts that said, for the same bullet, the slower one would never catch up to the faster one.

 

[GetReal]

"So the other day I had a conversation with someone who mentioned that on some bullets having a faster MV was slower at 1k. "

> > Every bullet will always be faster at the muzzle than at 1k yards. Rate of Velocity decline over distance will be due to any number of multiple factors.



"He said certain bullets can slow down much faster in the front part of the shot vs a slower bullet not having to work as Hard."

> > The varying effects of wind and humidity and Other factors causing a bullet to slow put aside ... BC is BC and is constant, and how well a bullet works over distance should remain a constant. As such - ignoring those other varying effects on a bullet - id think a single bullet would have a fairly consistent rate of velocity decline over distance. I'm spit balling that, as i'm no professional ballastician..


" After watching some videos of well respected shooters and gunsmiths saying a load will tune at 600 and not shot well at 1k makes me wonder is this is true."

> > The rest of this post aside , and other factors aside, and considering only ballistic coefficient, I would think that bullets of one specific BC are going to tune about the same at all distances ( other than closer to the muzzle before the bullet stabilizes.)

Edited, above.

 

[dellet]

Just because I like to point out the ridiculous, and why you should never use absolute words like never, go to your favorite ballistic calculator and check the velocities at 6000 yards. A variance of 100 fps muzzle velocity will all but disappear.

Often between 5-6000 yards the bullet starts gaining speed again. Whether this is true or a calculator error is way past my math skills.

But by using a trusted online trajectory calculator, I could prove that the OP’s original statement is true. Possibly earning a free drink or dinner in the local shooting trivia session. And that’s what internet bragging is all about.

ShootersCalculator.com | Ballistic Trajectory Calculator

Calculates the ballistic trajectory of a bullet fired from a rifle, handgun or other firearm. Produces a ballistic trajectory chart and table that shows the drop, velocity, kinetic energy, windage, and trajectory of a bullet.

shooterscalculator.com

 

[ShaunBrady]

Using exactly the same bullet, differences in muzzle velocity diminish with distance. That doesn't mean the earlier sins are forgiven though. The original velocity difference still shows up in the drop and rate of drop.

I ran a couple cases in both the linked solver and AB Analytics. It appears that speeding up effect occurs when the bullet trajectory becomes steep enough and the velocity enough lower than terminal that gravity becomes a larger force than drag. It's not seen at 6000 yards with bullets and velocities typically used for ELR, but it's an interesting bit of ballistics trivia for things like 30 caliber hunting rounds.

At a mile, shots that were 20 fps faster at the muzzle can easily hit lower as a result of small differences is bullet to bullet BC. The introduction of the LabRadar allowing real time velocity tracking made that effect obvious and started the pursuit of BC consistency.

The original post appears to be a version of hot water freezes faster.

 

[RegionRat]

Often between 5-6000 yards the bullet starts gaining speed again.

I'm tired after a long bike ride today, but I got a kick out of your post.

I tried to think of a way for a bullet to "speed up" after T(0) but the only way that happens is when it is dropped from altitude at a zero initial vertical and near zero horizontal velocity and accelerates due to gravity... so like from a balloon or hovering helo.

Once upon a time... I worked on some stuff for artillery that had an assist. It would fire from the cannon as normal, but then a propellant motor would also kick in and extend the range. You can imagine the cost of those rounds compared to regular ones....

Don't pull your betting money out, spend it on more ammo.

Merry Christmas and Happy New Year!

 

[dellet]

Using exactly the same bullet, differences in muzzle velocity diminish with distance. That doesn't mean the earlier sins are forgiven though. The original velocity difference still shows up in the drop and rate of drop.

I ran a couple cases in both the linked solver and AB Analytics. It appears that speeding up effect occurs when the bullet trajectory becomes steep enough and the velocity enough lower than terminal that gravity becomes a larger force than drag. It's not seen at 6000 yards with bullets and velocities typically used for ELR, but it's an interesting bit of ballistics trivia for things like 30 caliber hunting rounds.

At a mile, shots that were 20 fps faster at the muzzle can easily hit lower as a result of small differences is bullet to bullet BC. The introduction of the LabRadar allowing real time velocity tracking made that effect obvious and started the pursuit of BC consistency.

The original post appears to be a version of hot water freezes faster.

Part of the reason I chose the Shooters Calculator trajectory version is that it will provide maximum shot distance for the chosen cartridge. This is not something talked about very often and most people would be familiar with the warning on 22 LR that stated effective range of one mile. If you plug 22 LR into that calculator the. Joker starts speeding up at roughly 1850 yards and has a maximum range of 1999 yards. Kind of validates the warning label.

Other cartridges show the same velocity increase at different distances. 223 at 4000, 50 BMG at 8000 yards.

Where I first stumbled on to this was with subsonic shooting, generally with less than space ship designed shapes. Those bullets retain velocity for great distances.

Example Hornady 220 round nose compared at 1000/2400 fps. The 1000 fps bullet will be traveling faster than the 2400 fps bullet at just over 3000 yards. What probably helps is the gravity pull from a trajectory that is twice as high. 80,000 inches vs 40,000.

Again these are kind of absurd distances, but since slow bullets shed velocity at a much slower rate, there seems to be a point of intersection where the slow bullet overtakes the fast.
The tortoise and hare is true.

Now the only way this might happen is to shoot over a canyon so the bullet doesn’t hit ground before the slow bullet is faster than the fast one,

 

[ShaunBrady]

My latest way to abuse solvers is studying to death the effects of small changes in velocity and BC at ELR distances so I may have my nose in my own weeds. I see the speeding up effect you pointed out in the solvers, but it is an extremely small effect late in the game. Interesting, but not enough for the tortoise to ever catch the hare.

This is the difference in Velocities at each distance between the original 30 caliber example and a second bullet 10 fps faster.


The effect is there but appears very late and is so small a range card that only reports to whole fps doesn't always catch it.

This is the difference in time to each distance.



The hare wins at every distance. It keeps pulling further ahead, faster, as the distance increases.

I ran some rimfire cases just above and just below Mach 1 to try to catch the counter intuitive things that happen there. Similar results to the 308 example, yea, the slower bullet speeds up a small amount sooner than the faster bullet but it's not enough to overcome the earlier advantages. That started at ~1600 yards and died at 1850. The solver started giving error messages at about 250 fps.

Can you produce an example where this goes on long enough for the tortoise to catch the hare? It doesn't need to be anything real, just a set of circumstances where the same bullet launched a little faster arrives later.

 

[dellet]

As long as it doesn’t need to based in reality, I’ll give it a go two possibilities…
We all know that bullets go to sleep, just like the hare. If the higher velocity bullet goes to sleep, after the slow bullet has achieved the velocity advantage, of course it will catch up and pass.

The same bullet fired from two different cartridges, if the slower bullet is fired from a 6.5 creedmoor, without a doubt it will reach the destination faster than any other same bullet fired from the same Place from a different cartridge, at a higher velocity.

In reality, the slower bullet not only takes longer to get to the mythical speed swap, it also travels a greater distance to get there. So I can’t think of a a way for the slower bullet to ever arrive first. Caught with the wrong fable, maybe Alice in wonderland would have been more appropriate?

Then again, if one bullet is traveling east, and the other west……