How important is it to get a 50/50 mix with first and second runnings? I switch to a bigger mash tun last weekend and increased from 1.25 qt/1b to 1.5 qts/lb. I didn’t get as much absorption as my old system and ended up getting 7.5 gallons on first runnings and 4.5 on second runnings for 12 gallons preboil.
I like to get a bit closer than that, but overall kit’s not a huge deal. My goal is to keep first and second runnings within about a gal. of each other, but I do 5.5 gal. batches. When you do a bigger batch it’s harder to do since you need more mash water. IMO, it’s better to have the larger volume come from first runnings. As long as your efficiency was good, I don’t see a real problem with what you did.
Am I figuring my efficiency correctly?
20 2 row
1 lb crystal 120
1 lb crystal 10
22 lbs X 36 points per lb= 792
My OG was 1.056 at 11 gallons
Do I use the 12 gallon pre-boil to measure efficiency or the 11 gallon post boil?
You can calculate mash efficiency by using the pre boil numbers and brewhouse efficiency by using the post boil numbers. I t depends on what you want to know. For most people, though, they want to know the efficiency into the fermenter so they use post boil numbers. Using those, it looks like you got 77-78%…not bad!