Originally Posted by BWN
I usually take the total amount of water I need and split it in half but I think I need to get my first runnings to be half of the preboil volume instead of the strike water being half. I don't want to change too much at once because I want to figure out what is causing this. Any thoughts.
The way I read this it sounds like you're not accounting for absorption? Typical strike water volumes are, as said before, 1 - 1.5 qts. Per lb of grain and sparge water usually 2 qts/lb. I have lately been using less sparge water per brewpal's instructions and actually hit 82% on my last batch. (which I'm not considering a good thing because that means my OG was way high.) I'm not sure the 2 are related but maybe they are.
Make sure there are no dry grains when you mash in and stir like hell when you add your sparge water. Also make sure your sparge water is raising the temp of your grain bed to 165-168f. Some will say they sparge at a lower temp but once I got that worked out my efficiency shot up. So it helped for me.