Missed my first AGB SG...help

did my first AGB today. hit my mash temp of 154F and held for 60 minutes at that temp.

fly sparged my 4.5 gallons at 170F...drawing 1/2 quart per minute. got a little over 7 gallons of wort from 9.08 gallons of mash and sparge. water.

supposed to hit 1.042-44 preboil SG.....hit 1.34. had to add some malt extract to bring it up to 1.044 before boil.

thinking my grain crush for the wheat wasnt fine enough...looking for thoughts as to why i missed so my preboil SG by so much.

dunkle weizen:

Ingredients
Amt Name Type # %/IBU
8.0 oz Rice Hulls (0.0 SRM) Adjunct 1 4.3 %
6 lbs Red Wheat Malt (2.4 SRM) Grain 2 52.2 %
2 lbs Caramunich Malt (60.0 SRM) Grain 3 17.4 %
1 lbs Barley, Raw (2.0 SRM) Grain 4 8.7 %
1 lbs Cara-Pils/Dextrine (1.5 SRM) Grain 5 8.7 %
1 lbs Wheat Malt, Dark (9.0 SRM) Grain 6 8.7 %
1.00 oz Tettnang [4.80 %] - Boil 30.0 min Hop 7 13.3 IBUs
1.0 pkg Hefeweizen Ale (White Labs #WLP300) [35.49 ml] Yeast 8 -

how much water were you supposed to collect to get 1.042? was this a 5 gallon batch? too much water will lower your pre boil gravity.

eastoak said:

how much water were you supposed to collect to get 1.042? was this a 5 gallon batch? too much water will lower your pre boil gravity.

Click to expand...

Called for about 7gal preboil. That's about 1 gal loss to boil, and 1/2 gallon lost to cooling, and fermentation leaving me about 5.5 gallons.