How much grain capacity?

[barley ben]

This weekend, I'm thinking about converting my five gallon cooler to a mash/lauter tun. It's a five gallon round cooler with spigot. Just courious how much grain it can handle. And so I don't have to start another thread, what is an average water/grain ratio for a single step mash? Is 1.25 quarts per pound about right?

[Caffinehog]

Well, you can do many different quantities of water for each pound of grain. What you suggested would give the greatest yield, but I've done .75 quarts per pound for a double IPA. You can probably figure on maxing out somewhere around 12-15# of grain.