Energy/velocity calculator

Mark B provided an good Excel spread sheet and this data may be helpful to anyone that may want to play with Excel for your pellet rifle performance.

EXCEL FORMULA ACTION PERFORMED

=SUM(C5*0.3048) FPS to MPS, column C = FPS

=SUM(C5*3.28084) MPS to FPS, column C = MPS

=SUM(B5*C5*C5)/450240 FPE @ 450240, column B = pellet weight in grains, column C = FPS.

=SUM(B6*C6*C6)/450436.7 FPE @ 450436.7, column B = pellet weight in grains, column C = FPS.

=SUM(E5*1.3558) FPE to JOULES, column E = FPE

FPS = Feet Per Second, MPS = Meters Per Second, FPE = Foot Pounds of Energy.

To convert to Joules multiply FPE by 1.3558, Joules multiply .7376 = FPE

To convert meters per second, MPS, to FPS = 1M x 3.28084.

To convert feet per second, FPS, to MPS = 1F x .3048.
 
AGF6 said:
Originally posted by GardenPlinker, Sep 4, 2015



Easy enough to do yourselves... pellet/projectile weight x velocity x velocity divided by 450240 = result.

example for those wishing to test sub 12 gun law and not really recommended to run at this power.....

.177 pellet weighing 8.4 grains running at 800 feet per second = 11.94 ft/lb energy (fpe).... break this down a little bit...

8.4 x 800 x 800 / 450240 =11.94. If you reduce the velocity by 40 feet per second then you will have a gun with a muzzle velocity that isn't about to trouble any gun laws as such here is the relevant data...

.177 pellet weighing 8.4 grains running at 760 feet per second = 10.77 ft/lb energy (fpe)....

8.4 x 760 x 760 /450240 = 10.77.

This is why pellet weight is so important... that .177 pellet weighing 8.5 grains travelling at 800 feet per second is going to get you in a shitload of trouble..... 8.5 x 800 x 800 / 450250 = 12.082 ft/lb (fpe)...

it only takes 0.1 grain which is about 0.007grams to make you a lawbreaker.
Click to expand...
I have in the past tried to explain these very laws of physics to people who follow a different sport that uses low powered airguns for millsim game play and they just don't understand how the weight affects the resulting energy creep as its termed and how by "tuning" as they call it, can lead them to a firearms offence very quickly.

You hear these asking how to get a higher weight BB to travel faster as in their heads, a 0.25g BB travels slower but they want to still have the near maximum 350 fps that these guns generate and don't understand how this is making them illegal.

I tried to show with simple diagrams why this is and it was lost on them.

The same people also go airgun shooting and again, want their air rifles to output the maximum allowed, some guys have changed the calibration of the regulator so that they get more than the 12fpe at the muzzle and don't see anything wrong in doing it...

I just wish that ranges would like in airsoft, require a muzzle velocity check and then educate these rare breeds of cretin in the laws that regulate these weapons, they are restricted for good reason because they may well be airguns but they can still kill a person (esp children) and airsoft weapons can blind a person easily and point blank and there have been recorded deaths form airsoft guns.

The issue is that you can have a sport that is regulated and you can lay out the law but there will always be a core number of people who ignore these regulations and do what they like because they feel that the rules don't apply.

Its that old saying, you can lead a horse to slaughter but you can't make it shoot itself.
 
This is quick and easy . Probably the quickest for simple ft lb
Values .
geoffwilsons.co.uk

Airgun Power Calculator

Use the airgun power calculator below to work out your air gun's foot pound (Ft Lb) power. Just input your pellet weight (grain - not grams) and muzzle velocity (ft/sec). Pellet Velocity: (in fps) Pellet Weight: (in grains) GO
geoffwilsons.co.uk geoffwilsons.co.uk
 
Jamp said:
Use this one, multi applications, PCP Fills: Easy BC, ect.
works on all platforms..
MERO
Click to expand...
I use KECalc from the programmer of Mero. On my phone so works where I can't get a signal to use an online one .

KECalc: A Kinetic Energy Calculator

gpc.fotosoft.co.uk gpc.fotosoft.co.uk


Screenshot_20240903_235328_KECalc.webp
 
Hello, I can see its been a while since this thread was used so sorry for raising a old thread.
However I'm looking for a spreadsheet where you can enter 2 pellet profiles at the same time. For me its actually a pellet and a slug, I'm looking for the crossover for impact ft/lbs.
I have done a forum and web search and come up with nothing, does anyone have one they could share? Thank you.
 
Thank you, however I'm looking for some clever person who has say a excel sheet that allows to plot the trajectory of 2 projectiles at the same time.
 
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