Cooler Mash Tun - False Bottom vs. Copper Manifold

I've got a 7 gallon Rubbermade cylindrical cooler and I'm starting to gather materials to convert it to a mash tun.

I'm trying to figure out the pros / cons of a plastic false bottom vs. a ring copper manifold...

I've got a copy of Palmer's How To Brew and it sounds like if you make the ring manifold where 50% of the volume is outside and 50% is inside, "a single ring is more efficient than a false bottom until the false bottom diameter is at least 80% of the tun diameter."

Anyone with experiences using a ring manifold vs a plastic false bottom want to chip in? I'm looking forward to doing all-grain batches but I'm not sure which to go with.

Thanks!

 

I use a manifold that covers almost the entire floor of my mash tun/everything pot. It increased my efficiency. It makes sense about the false bottoms though. If there isn't enough liquid space under it you wouldn't get very efficient sparging. Water likes to take the path of least resistance so if your false bottom isn't big enough it basically funnels everything to a center point with out coming into contact with the grist along the outside perimeter of the false bottom.