Original and Final Gravity undershoots

I'm a comparative AG novice, and have had a pretty good time producing a few batches using found recipes from this site and others and also some clumsy amateur attempts using http://beercalculus.hopville.com/recipe recipe calculator.

I'm generally pleased, as are my wife and friends with the results so far, but of course there's always plenty of room for improvement. I'm a bit flummoxed to date about the OG and FG numbers I'm getting from by recipes. They all seem to fall a bit short on the OG side and finish out on the low end of the FG. So, if the recipe predicts an OG of 1.064 and an FG of 1.016, I'm more likely to get an OG of 1.058 and an FG of 1.010 or similar. I know that the final ABV will be similar, but I suspect my beers could be richer if they finished out a little higher. Not that, they're all that bad.

I think my hydrometer is pretty accurate. I have tested it in 60 degree tap water and it reads exactly 1.00. I'd appreciate your thoughts on what might be contributing to this situation.

Are your temperature, weight and volume readings accurate ? How is the crush of the grain ? Regarding efficiency, unless you are getting terribad efficiency (50% or less) and wasting tons of grains, I wouldn't worry about lowish numbers. Consistency is good since repeatability is at the core of being a better brewer.

Since you are using Hopville, I assume you haven't touched the efficiency % on the right side of the calculator. Bump that down from its rather optimistic 75% down to your own levels (65% ?) and reevaluate afterwards if there is a problem.

I also wouldn't base my projected FG readings on any brewing software. That's all experience baby ! You have to take into consideration the grist (more sugar = more attenuation), the yeast strain, the pitching temps, the mash temps, yeast viability, etc.