I was feeling extra lazy today, so I did a "no sparge" instead of my typical batch sparge. I've been leary of trying this because my mash tun is only 36 quarts. I had 11 lbs of grain and I filled the cooler to the brim with about 7.5 gallons of water. I collected about 6.25 gallons in one runnings and got an efficiency of 68%. My usual batch sparge efficiency is 75%, so this wasn't too bad. My 5.25 gallon batch was about 1.052 OG...which is about the max for my little mash tun...but 70% of the beers I brew have an OG around this level. Might have to do this more often.