I brewed this last night, it was my first attempt at a higher-gravity beer like this. However, I missed my O.G. by a mile, and I'm hoping someone might be able to offer a possible explanation.
I brewed the recipe as listed, with 2 very minor modifications: I added 1 lb of dextrose to the boil, and I used 1.75 oz of Warrior for the bittering addition instead of Magnum.
As I was chilling (I recirculate through a plate chiller back into the kettle until I reach 70° F), I took a gravity sample. It was 1.060.
Huh!?! The recipe claims an O.G. of 1.077, and I added an extra pound of dextrose, so I should've been even higher.
This is the most grain I've ever mashed with, and BeerSmith directed me to mash with 19 quarts of water, at 148° F. I stirred quite well (or so I thought), and I even popped the lid and gave it another good stir 20 minutes into the mash (I never do this). So how did I miss my O.G. so badly? Where did all those extra sugars go?
I batch sparged with 4.75 gallons of 170° water.
I'm quite disappointed, but I'm hopeful the beer will still turn out nicely.