20 gallon partial mash

All,
I've energized the brew club I've recently joined to have a "big brew" day. The goal is to brew 20 gallons of beer, to be split into 4+ batches, each using a different yeast. We're brewing an English Brown Ale.

To get to 20 gallons of beer, my thought is to use LME as the base malt (NB has Maris Otter extract, so going to try this) in the keggles (2 keggles), and put the grains in my mash tun - about 12 lbs. of grains.

The grains will be:
UK Brown Malt 7.50 lb
UK Munich Malt 3.00 lb
UK Caramalt 2.50 lb

My question is this: How do I determine the right mash temp for the best conversion? Designing Great Beers has a mash temp guideline, but this is for all-grain, and I'm not sure if this same temp (151) will work as well for these specialty grains.

Thanks,

Pete

Yup the same temperatures would apply so 151F would work just fine. You can use a higher saccharification temperature if you want to end up with a sweeter beer, lower if you want a drier one. Personally, I would shoot closer to 153F as you do not want the beer to finish too dry.

Thanks. I had one of these last night (http://adnams.co.uk/beer/our-beers/adnams-southwold-bitter/), and it was nice, but too dry for me.

Pete