Reason for inconsistency in specific gravity of calcium choride added to water
When you say, "of products", do you really mean "of the solution"? If so:

The solvent mass and the solute mass add up to the mass of the solution.  

But solvent volume and solute volume often don't add up to the volume of the solution. This is because the forces between molecules in the solution are different from the forces between molecules in the pure solute and the pure solvent.

In your solution, the calcium ions and chloride ions attract water molecules around them. The water molecules are packed more tightly than they would be if the ions weren't there. That can increase the density of the solution relative to the total volume of the unmixed solvent and solute. Another effect is that the ions in solution are packed less tightly than they are in solid $\rm CaCl_2$.

You can see which effect wins by dumping some calcium chloride into a volumetric flask. Fill the flask up to the mark with water, and then mix until all the calcium chloride dissolves. The solution probably doesn't quite come up to the mark anymore, because the calcium and chloride ions have drawn the water molecules in around themselves, making the solution denser than it would be otherwise.

More detail than you may want below: 

The volume of the solution $V$ is given by the following equation:

$$V = n_1 \overline{V}_1 + n_1 \overline{V}_2$$

where $n_1$ and $n_2$ are moles of calcium chloride and moles of water in the solution, and $\overline{V}_1$ and $\overline{V}_2$ are the partial molar volumes of the calcium chloride and the water. 

These partial molar volumes are actually derivatives of the volume of the solution with respect to moles of calcium chloride ($\overline{V}_1 = \partial V/\partial n_1$) and with respect to water ($\overline{V}_2 = \partial V/\partial n_2$). They are related to each other (when one rises, the other falls) and they vary with the composition and temperature of the solution in a rather complicated way.