Beersmith 2 and where did I go wrong?

[Homercidal]

Had a brew day yesterday. Entered all my information into BS and planned a single batch sparge.

BS says 3.44 gallons for mash, and 5.88 for sparge.

Using weight to measure the water (used 8.14 lbs per gallon, instead of teh correct 8.34, but the difference is minimal).

Should give 9.32 gallons, minus absorption leaves 8 gallons (ish).

Mashed for 75 minutes and boiled for not more than 1 hour.

Got about 4 gallons of cooled wort in the fermenter.

Never had a problem like this. I am dumbfounded as to what happened.

Any ideas? (other than my scale is off...)

 

[Homercidal]

Forgot to add that it was a hefeweizen and the grain bill was 7 lbs white wheat and 4 lbs Pilsner.

 

[RoadKing]

The numbers seem right. Did you measure volume in your boiler?
And what is your boil off rate? I boil off 1.90 Gallons per hour.

 

[Homercidal]

I estimated about 2 gallons boil off, so I ran the numbers to end up with 6 gallons. I figured with the humidity and heat I might end up with a little extra, and no big deal.

I did not measure the water in the BK. I've never had to before. Kind of wish I had so I could know what happened.

My OG was 1.060 and was supposed to 1.050, so boil off could have been a reason. Or I got much better efficiency. Either way, I added some water to increase the volume and lower the gravity. It's bubbling away.