Originally Posted by solusveritas
How do I find the target gravity? Is it guess work, or is there another way to calculate it?
I think you're pretty close with this statement...perhaps it's not fully a guess, but it's at best an estimate. If your yeast has the alcohol tolerance to fully dry out your mead, then the FG is probably about 1.000 (in reality many meads go slightly lower; ie, 0.995-0.999).
If you're starting at an OG where your yeast potentially won't be able to fully ferment out before reaching alcohol tolerance, you might need to play with an ABV calculator to estimate what the residual gravity would be at that point.
Still, the actual alcohol tolerance of a yeast is highly variable, and has a lot to do with the make up of your must and other environmental variables.
I'd venture to say unless you have a good number of batches under your belt, and even better a good number of the same exact recipie, all with very controlled conditions, estimating your FG is probably best considered an educated guess.
Bottom line is if you want to do SNA's, you can probably pick any random point after the first initial burst of fermentation has completed to add the additional nutrients...