Converting AHS recipes for batch sparging

I'm doing my second all grain recipe from Austin Homebrew and I'm trying to figure out how much water to use for a batch sparge. The instructions it comes with just say to use 5 gallons and fly sparge until I run off 6.25 gallons.

I'm assuming I would just subtract the first runnings volume from 6.25 and use that amount for the sparge? Is grain absorption an issue during the sparge? I was thinking that after the mash the grains will have already taken in all the water they can so so, if anything, it would be a lot less during the sparge.

 

I would down load brewtarget or the Beersmith free trail and plug in your recipe. It will calculate volumes for you

 

Awesome thanks

This is a session strength beer so it's only using 8.5 lbs of grain, so if I go with 1.25 qt / lb for the mash that's only 2.65 gallons. If 8.5 lbs absorbs about a gallon the first runnings will only be 1.65 gallons. So I would sparge with 4.6 gallons? I'm guessing I'll need to break that up into two batches?

 

Right,

Two other things to consider:

1. You may lose some of the first runnings to dead space in the MLT.
2. You may want to collect a bit more than 6.25 gallons total to account for dead space in the kettle and trub.

I'd prepare about 1 gallon more sparge water than you think you will need. It's better to have too much than too little. The next brew you should have a better idea how much water you will need (if you take notes).


-a.