Batch sparge FG Question

Hi all,
Any batch spargers out there want to have a shot at this?

I have read Denny's great article on batch Sparging and have put his method into practice.

The question I have is "What do most people get in the way of SG readings for their final run off?"

All of the beers I have done with this method use a double batch sparge but I have noticed my final runnings are up around 1.020, is this normal?
My efficiency into the kettle is around the 70% mark, but I was wondering if I am losing some of the good stuff to the mash.
What is the SG of most peoples final runnings?

Cheers
Andrew

I don't take reading for each run off.

I just check the kettle gravity.  I am getting 75% in the kettle.

I guess I don't worry about the SG of the run off if I hit my kettle and OG numbers.  I usually do.

Oh,  I only to one run batch sparge after I drain the tun.

Don

The bottom line is assuming you are using 10 pounds of grain, approx 1.2 gallons will be retained by the grain,  1.2 * 20 (1.020 final runoff) gives you about 22-23 total gravity points out of 370.  That means that you are leaving about 5% of the potential behind so you are 95% into the boil (assuming no dead space losses).  Sounds pretty good to me.  Don't worry about it.

Fred