Hi Burrman,

Pilou shows a balance scale, which permits weight to be measured, using known mass counterweights.
So the result is that the earthly weight is given by the balancing mass. (Different on mars?)
The gravity at the earth worksite may be considered to be constant, so a spring scale or an electronic scale would also measure the mass.
So talking about gravity just makes for confusion.
The common practice of equating "weight" with "mass" will work just fine in the current scenario. Using label of "mass" would be more scientifically correct.

Anthony is right-on about density involvement.
I think that the weight(mass) to volume calculator uses a stock density for lead. A custom density ability would be nice, but absent custom density,
a conversion equation is needed to compensate for the different density of the batch of lead being used, or to compensate for pouring conditions discrepancy.

Compensation Equation:
**********
(corrected Volume in cu_in) = (Volume, in cu_in, from the conversion program) * [(desired weight, in oz) / (actual weight, in oz, of test pour)]
**********

0.2774 cu_in = (0.3051 cu_in) * (2.0 oz) / (2.2 oz)

So 0.2774 cu_in should be the volume of the corrected mold.

Note that (0.3051 cu_in) / (2.2 oz) is the reciprocal of the apparent density of the lead batch, based upon the initial test pour.

aqua_calc has weight to volume and volume to weight calculators.
(2.0 - (2.2 - 2.0)) = 1.8 oz, to yield from the calculator your volume of 0.2746 cu_in, which is close to the above 0.2774 cu_in.
(I think that the 1.8 method may not be quite the right way to make the compensation(?))

I say "apparent density" because "pouring conditions" is also talked about, which is in effect captured in the reciprocal density in the above Compensation Equation.
(note that ounce, oz, is a mass measure, NOT fluid ounce)

- Brian

max had a volume calculator with custom densities???...

Temperature and Bouyancy make a miniscule difference?