Huh? All grain OG higher than recipe calls for?

[Silverbullet]

Just brewed up a Chocolate Milk Stout from NW and the estimated pre boil gravity was 1.044 w/Beersmith. Hit that dead nuts on and was very please. Estimated post boil gravity called for 1.049 (per NW recipe) and I hit 1.060 with between 5.25 and 5.5 gallons going into the fermentor, which is exactly what I had planned. Not that I'm complaining, but why is my gravity so much higher than the recipe called for?

I normally fly sparge to increase efficiency but just picked up a cheap corona mill and use that for the first time running pre-crushed grains through the mill once since I had issues with bad crushes in the past. I got lazy this time and decided to batch sparge instead of fly sparge as usual. If anything, I figured my gravity would be hurting as a result. According to beersmith, my mash efficiency was 91.7% and my overall efficiency is 81%.....WAY higher than my usual low 70s. Does a good crush really make THAT much of a difference??

 

[chickypad]

If your efficiency was that high your pre-boil gravity would also have overshot if your volumes were on. OG of 1.060 at 5.25 gallons final volume would have put you at about 7 gallons of 1.044 pre-boil. Is that what you started with?

 

[Silverbullet]

I'd have to double check my notes but I think it came in around 6.25 gallons pre boil (when I took gravity reading of 1.044 but realized I should have added more sparge water) and I topped it up to close to 8 gallons before I started the boil and boiled that down enough to where I ended up with just under 5.5 in the fermentor.

 

[chickypad]

You need to know what your starting volume is to figure out your target pre-boil gravity. Anyway, sounds like maybe the kit volumes and Beersmith volumes don't match. What did Beersmith say your final OG was supposed to be at 5.5 g?

edit: oh just saw you topped off too before the boil. That could have thrown off your pre-boil gravity if it wasn't mixed well.

 

[Silverbullet]

Ahhhhhhh, I think this is the obvious missing piece of the puzzle (few too many homebrews apparently). Tried something new today as well. Think of it as a BIAB in the mash tun. Used my regular 15g mash tun but lined it with a BIAB type bag. Halfway through the boil I pulled the bag and grains (from mash tun) and had what appeared to be just under a gallon of clean wort. I had dumped that in with the boil and that surely spiked my gravity. Almost forgot I even did that, and that didn't make it into my notes (inserting them now!). Mystery solved. Jeez...