Here's what I got with my adjustable brass powder measure set at 100 grains volume. Filled it with each type of powder, tapped the side of the measurewith a pencil six times to settle the powder (it settled about 1/4"), then filled it again to overflowing, tapped it down again twice, then leveled it off and weighed it.

Goex FFGweighed 110 grains even.
Pyrodex RS weighed 78.0 grains.
Pyrodex Select RS weighed 76.7 grains.
Triple Seven FFG weighed 77.8 grains.
Triple Seven FFFG weighed 87.0 grains.