H&N Ballistic Calculator inaccurate

[Buddy2023]

I went to H&N's website to use their Ballistic Calculator and punched in a few numbers and the results looked suspicious so I checked their numbers with my calculator using the Mass x Velocity Squared divided by 450240 formula and there was over a 15 ft lb difference between my calculations and theirs with their results being incredibly low, for instance it said a 8.4 gr FTT traveling 1,200 fps only produced 11.34 ft lbs which is horribly inaccurate, my calculator showed the results as 26.87 ft lbs. Just a heads up folks take care.

 

[Stubbers]

Good find. Should contact them and inform them something is off. I got 8.54 gr @ 1200 fps giving 22~ FPE when using their calculator where as it should be 27.

-Matt

 

[Bladesx]

Muzzel energy vs Terminal energy?

 

[Stubbers]

Muzzel energy vs Terminal energy?

They don't ask your target distance.

-Matt

 

[Buddy2023]

Muzzel energy vs Terminal energy?

Their calculator lists (muzzle velocity)

 

[HN Sport]

The specification of the "velocity" is meant a little differently:
Many manufacturers do not specify the muzzle energy for their airguns but rather a muzzle speed. The measurement is of course made with a very light lead pellet to achive a hight value. So if you only have this information for your weapon, you can enter it and the calculator will then estimate the muzzle energy based on a light pellet. Unfortunately, you cannot enter a measured speed of the specific pellet (here the FTT).
I am sorry for this confusion.

 

[Buddy2023]

The specification of the "velocity" is meant a little differently:
Many manufacturers do not specify the muzzle energy for their airguns but rather a muzzle speed. The measurement is of course made with a very light lead pellet to achive a hight value. So if you only have this information for your weapon, you can enter it and the calculator will then estimate the muzzle energy based on a light pellet. Unfortunately, you cannot enter a measured speed of the specific pellet (here the FTT).
I am sorry for this confusion.

Thank you for your response, my issue was your calculator was giving muzzle energy numbers that were several foot pound lower than what they should be, I checked this with my personal calculator using the Mass x Velocity Squared divided by 450240 formula. I don't believe it's anything I'm doing wrong, your calculator is very straight forward? Your calculator shows a .177 8.54 FTT traveling at 1,200 fps as producing a muzzle energy of 22 ft lbs, the actual muzzle energy should read 27.31 ft lbs.??