Muzzle Energy Math

[Vern Humphrey]

by converting the weight of the bullet into Kg, the conversion to mass from weight is already incorporated...

No, a kilogram is still a unit of weight, not mass.

So wouldn't a simple: (Bullet weight/7000)/2.205 = a proper mass unit for conversion into Joules?

Then a quick (fps)(.3048) for the velocity.

Then Joules x 0.74 = ft-lbs

You seem to be mixing the metric and English systems.

The use of Joules in this approach converts weight to mass.