FP are equal; give me speed of a light pellet; give me a heavier slower pellet?

[45flint]

All things being equal I may be wrong but I would want a heavier pellet for hunting. More bullet mass means more kinetic energy and that equals to more damage.
But on the other hand a lighter pellet you will have more range I would think. So their you have it! I don’t have a clue. This will be interesting!!

I think your reasoning is what I have heard, but the energy is really the same?   Its only different if they are traveling at similar speeds?

[45flint]

Anyway, it really does not matter.  They will both kill pretty much the same, deoending on whether you can hit the kill zone.

I’m not worried about it, just a intellectual exercise.  The difference in energy between the Chart and the Chairgun Pro program at 50 yards is dramatic.  Both can’t be right?  If the Chart is from observation it would carry more weight?  Assume the Chairgun Pro is calculating using math formulas?

[justinp61]

Using your highest velocity's I entered the info in Chairgun Pro this is what it came up with. You didn't specify which Benjamin pellet and there are two that weigh 14.3 so I used both. The heavier pellet has less drop and more energy. Accuracy being equal which one would you choose?

H&N 11.42                              25yrd 0, drop at 50yrds.
Muzzle: 19.46                                      3.09"
25 yrds:11.62
30yrds:10.49
50yrds: 6.96

Benj. Diablo
Muzzle: 20.1                                        2.84"
25yrds: 15.11
30yrds" 14.28
50yrds: 11.41

Benj. Cyl.                                           
Muzzle: 20.1                                        2.96"
25trds: 14.74
30yrds: 13.87
50yrds: 10.87

Interesting may be better if you didn’t take the extreme but maybe 8 pumps?  Your calculations from the program are at odds with the chart above which shows the energy the same at 25 yards and 50 yards? The Benjamins were the 20 cal. cyl. only ones made.

I think the very small difference in drop is that in my table the Benjamin at 12 pumps had a little more energy.  At 8 pumps it would be the opposite?

The chart you posted the link to shows the lighter pellet starting with more energy than the heavy one.

Tomorrow I'll play with it some more, have to work tonight. BTW Chairgun shows two .20 Benjiman 14.3gr pellets, i don't shoot .20's so I don't know.

[justinp61]

45flint here's the link to download Chairgun Pro. It's not a end all do all but it is fun to play with, like any other program it's only as good as the data input is.

https://us.hawkeoptics.com/chairgun.html

[45flint]

45flint here's the link to download Chairgun Pro. It's not a end all do all but it is fun to play with, like any other program it's only as good as the data input is.

https://us.hawkeoptics.com/chairgun.html

Thanks

Found this when reading about bullets mass vs velocity.  Velocity is more powerful in calculating kinetic energy.

“It really comes down to the physics, bear with me here...

Kinetic energy is what they list as "muzzle energy", using the muzzle velocity and the bullet weight. The equation is as follows for kinetic energy:

Energy = 1/2 * Mass * (Velocity)^2

Because velocity is squared in that equation, if you double the velocity, the energy is multiplied by 4, while if you double the mass, the energy is simply doubled.”

[rsterne]

If you start two pellets out with the same muzzle energy, the one that arrives downrange with the greater muzzle energy will be the one with the better Ballistic Coefficient.... The BC is a measure of how quickly the pellet loses velocity, and hence energy....

Chairgun lists the BC of the H&N FTT 11.5 gr. pellet as 0.025, but the Beeman H&N Match as only 0.016.... It shows the BC of the Benjamin 14.3 gr. cylindrical pellet as 0.023, and the Benji Diabolo as 0.025.... The only place your two pellets have close to the same energy is at 7 pumps.... Here is what ChairGun gives.... I used the two pellets that had the same BC = 0.025....

H&N FTT @ 736 fps.... @ 25 yd = 650 fps (10.80 FPE)…. @ 50 yd = 576 fps (8.46 FPE)

Benji Diabolo @ 660 fps.... @ 25 yd = 584 fps (10.83 FPE)…. @ 50 yd = 517 fps (8.48 FPE)

However if you are using the Benji Cylindrical (BC = 0.023) @ 660 fps.... @ 25 yd = 578 fps (10.80 FPE)…. @ 50 yd = 506 fps (8.12 FPE)

As you can see, the lower BC has a bit less FPE as it goes downrange.... If the BCs were more dramatically different so would be the energy downrange.... Generally, heavier pellets have a better BC than light ones if the shape is the same....

Bob

[45flint]

H&N FTT @ 736 fps.... @ 25 yd = 650 fps (10.80 FPE)…. @ 50 yd = 576 fps (8.46 FPE)

Benji Diabolo @ 660 fps.... @ 25 yd = 584 fps (10.83 FPE)…. @ 50 yd = 517 fps (8.48 FPE)

However if you are using the Benji Cylindrical (BC = 0.023) @ 660 fps.... @ 25 yd = 578 fps (10.80 FPE)…. @ 50 yd = 506 fps (8.12 FPE)


This makes sense.  It to me is what I would expect,  thanks

[45flint]

45flint here's the link to download Chairgun Pro. It's not a end all do all but it is fun to play with, like any other program it's only as good as the data input is.

https://us.hawkeoptics.com/chairgun.html

Cool program. Been playing with it

[Vintage Streak]

Is all this theoretical or has it been measured by any means indicating how much of a wallop different weight pellets deliver at different distances. Theory is sometimes one thing real world another. Just wondering.

[45flint]

Is all this theoretical or has it been measured by any means indicating how much of a wallop different weight pellets deliver at different distances. Theory is sometimes one thing real world another. Just wondering.

Theory is always tested by doing, both are fun.  Much of this only influences long shoots well beyond my backyard.  But it’s all interesting.  Ballistic Coefficient of different pellets is interesting but it’s influences for most of us is immaterial? 

[Vintage Streak]

What I was looking for is a link to where an actual test  was done to prove or refute the actual delivered energy upon impact.

[rsterne]

Ballistics Coefficients come from real world testing, where the velocity downrange is measured and compared to the muzzle velocity.... It is very important in terms of the delivered energy and momentum downrange.... For example, a wadcutter like the H&N Match has a much lower BC of only 0.016.... Using that instead of the 0.025 of the H&N FTT, starting at the same MV of 736 fps, we get....

MV = 736 fps.... @ 25 yd. = 607 fps (9.41 FPE)…. @ 50 yd. = 501 fps (6.41 FPE)….

Just changing the BC from 0.025 to 0.016 drops the energy at 25 yards by 13%.... and at 50 yards by 24%.... In addition, the pellet, moving slower, will drop more....

Here is a link to the most extensive BC testing currently available.... https://hardairmagazine.com/ballistic-coefficients/

Bob

[Vintage Streak]

Thanks, I find it interesting even though I don't do the math I just kill paper targets. 

[45flint]

Ballistics Coefficients come from real world testing, where the velocity downrange is measured and compared to the muzzle velocity.... It is very important in terms of the delivered energy and momentum downrange.... For example, a wadcutter like the H&N Match has a much lower BC of only 0.016.... Using that instead of the 0.025 of the H&N FTT, starting at the same MV of 736 fps, we get....

MV = 736 fps.... @ 25 yd. = 607 fps (9.41 FPE)…. @ 50 yd. = 501 fps (6.41 FPE)….

Just changing the BC from 0.025 to 0.016 drops the energy at 25 yards by 13%.... and at 50 yards by 24%.... In addition, the pellet, moving slower, will drop more....

Here is a link to the most extensive BC testing currently available.... https://hardairmagazine.com/ballistic-coefficients/

Bob

Bob thanks for this data, very interesting. 

For one there seems to be no testing of 20 cal. pellets? 
But look at a common pellet I use all the time, RWS SuperDomes in .177 and then in .22.  The ballistic coefficient of the lighter .177 is greater than the .22.  The opposite of what I was hearing: Heavier pellets have better BC?  Goes to show you, you need to shoot them not just do the math?

[rsterne]

There are MANY variables that go into the BC, the weight is not the answer unless you are comparing pellets of the same caliber.... In different calibers you need to use the Sectional Density, which is the "weight per unit area".... The SD is also one of the two main criteria affecting penetration in a soft target, the other being velocity....

The BC has two main factors, the SD and the shape, expressed as the Form Factor.... They are related by.... BC = SD / FF …. so even if two pellets have the same SD, they can have a different BC because they have different shapes.... To make things even more complicated, the BC of a pellet is not a constant, it depends on the velocity.... and to some extent the gun it is fired from.... because the shape of the pellet changes from the pressure propelling it down the bore.... Check out this photo....



Those are JSB Exacts, the 2 on the left were fired, while the 2 on the right were just pushed through the barrel with a dowel.... How much the skirt changes shape depends on the pressure, the hardness of the lead, and the thickness of the skirt.... The bottom line is that the BC is the governing factor in how the pellet slows down as it travels downrange.... However, the only way to get the exact BC for your gun and pellet is to test it.... The published numbers are only a guide.... Having said that, a wadcutter will have much poorer downrange performance than a round nosed pellet of the same weight, and pointed and HP pellets are somewhere in between.... and when you compare pellets of similar shape and different weight (in the same caliber) the heavier one should have a higher BC....

Bob

[Vintage Streak]

So when all this pellets being shot are they weighed and measured to make sure your data is correct. Do you just get them out of the tin. I don't know if this factors in to the equation
.

[rsterne]

There will obviously be some slight difference from pellet to pellet.... I believe HAM shoot 10 pellets through their LabRadar and take the average near and far velocities to use for their BC calculation.... There is probably more variation in the velocity from shot to shot in most guns than the change in BC from pellet to pellet....

Bob

[Whirligig]

Here is my comparison of two pellets in my Sterioded Benjamin-Sheridan Silver Streak in 20 cal.  The H&N 11.42 grain and the Benjamin 14.3 grain.  The test showed basic physics works: energy is about equally but speed changes.  If accuracy is the same what would you prefer?  My assumption would be target shooter wants the speed and hunters want the heavier pellet?  But energy is the same? 
 

Pumps.           FPS H&N 11.42.                   FPS  Benjamin 14.3
3.                  523.                                    471
4.                  592.                                    528
5.                  648.                                    583
6.                  697.      12.32 FP.                 610.     11.84 FP
7.                  736.      13.74.                     660.     13.84
8.                  776.      15.27.                     686.     14.95
10.                829.                                    735
12.                876.      19.46 FP.                 794.      20.02 FP

Wouldn't the "speed of light" pellet have infinite mass, and therefore a higher FPE than the slower, heavier pellets?

Oh, wait.

Never mind.

-Whirly

[45flint]

Here is my comparison of two pellets in my Sterioded Benjamin-Sheridan Silver Streak in 20 cal.  The H&N 11.42 grain and the Benjamin 14.3 grain.  The test showed basic physics works: energy is about equally but speed changes.  If accuracy is the same what would you prefer?  My assumption would be target shooter wants the speed and hunters want the heavier pellet?  But energy is the same? 
 

Pumps.           FPS H&N 11.42.                   FPS  Benjamin 14.3
3.                  523.                                    471
4.                  592.                                    528
5.                  648.                                    583
6.                  697.      12.32 FP.                 610.     11.84 FP
7.                  736.      13.74.                     660.     13.84
8.                  776.      15.27.                     686.     14.95
10.                829.                                    735
12.                876.      19.46 FP.                 794.      20.02 FP

Wouldn't the "speed of light" pellet have infinite mass, and therefore a higher FPE than the slower, heavier pellets?

Oh, wait.

Never mind.

-Whirly

The Einstein Pellet

[Killo Coonadillo]

I still have a hard time understanding the pointed pellets have a lower bc than domed?
Someone who wants to try to put it in simple terms explain.
Is it something to do with the skirt or what?

I know pb'ers bullets, don't the sharp pointed do better than round nose?

This stuff is Greek to me...no wait... I know some Greek and still this is more a mystery...