Hi all,
I did my first BIAB today, my first all grain and my third brew ever. It was a mixed experience. The brew was a clone of Ballast Point Sculpin IPA, a great blonde 7% ABV hop bomb. I started with a 14 lb grain bill and mashed out in 4.3 gal 151 degree water for an hour. I couldn't do a full volume since my pot is 7 gal. This all seemed to go well despite missing my temp by a couple degrees, but that was corrected with a little heat and stirring. I gave the bag a good squeeze and then transferred to a batch sparge at 168 (missed my 175 target temp again but didn't correct it this time). I combined the sparge and mash and took a sample to cool for SG. I then did my boil but I felt my volume was about .75 gal lower than I predicted with 0.08/lb absorbed by grain. So, about 30 min into the boil I added .5 gal water. Finished my boil and cooled and then remembered to take my preboil SG and my OG. Those came out at 1.060 and 1.064 respectively, a ways from the expected of 1.068 and 1.076. At 60% efficiency I was pretty disappointed.
I had two other problems. My wort has a huge amount of trub that didn't want to settle out. I didn't use the finest bag, probably should have been finer. I also came out about 0.5 gal short of my target volume. I thought I started with 6.3 gal to end at 5.4 gal (with 0.4 gal yeast starter). I guess I may have missed one of my 0.75 gal water additions when measuring. I ended up with 4.7 gal even after about .9 gal of additions.
Anyway, I should be fine but I sure would like to know where the water went and why the low efficiency.
Curt