Mash water

I’m new to all grain.  I’ve read a couple books that both say to use 1.5 - 2 qts / lb for mash water.  But beersmith, and people on these forums seem to recommend 1.25 most often.

What difference does it make?  It seems like using 1.25 and sparging with more water would get you better efficiency.  Is that right?  Is there something else I’m missing?

I usually mash at 2:1 in a recirculation direct fire mash tun. I batch sparge and recirculate that too for about 15 minutes. I track brew house efficiency only, and normally I’m at 75% +/-5

I use a 1.75:1 ratio and batch sparge.  For most of my recipes, I end up mashing with just slightly more water than I sparge with and get anywhere from 70-78%.

Pretty much the same for me.  ~ 78- 80% brewhouse efficiency.

1.25/lb is good if you are doing a step mash. thinner mash (to a point) will increase conversion efficiency and can help with some efficiency problems. I generally aim for 2:1 although by the end of a no sparge batch I have all the water in there.

BS doesn’t recommend it, it defaults to it.  Don’t let BeerSmith push you around.  YOU get to tell IT what to do, not vice versa.

Yes if you would prefer a 2qt/lb ratio to be your default in BS it’s easy to change.  It’s software it has to default to something ;D If you open the mash profiles you can change (and save) them.  Most of mine are set to 1.75 for their defaults.

Ha, I like it!  I’m telling that software where to go!

If I’m doing a step mash, I’ll shoot for somewhere around 1.33-1.5qt/lb for the first rest, then after the second infusion is added, it ends around 1.75qt/lb or so maybe. For single infusions, I shoot for 1.5-1.75qt/lb.
The thinner mash is easier to stir/mash in, I think is a big benefit.

Mash ratio simply doesn’t matter much at all, especially if you fly sparge.  One advantage with higher qt/lb ratios is that the more water you use, the better your mash will hold the heat and prevent the inevitable cooling into low to mid 140s.  With a batch sparge, if you want to improve efficiency for big beers, mash super thick 0.8-0.9 qt/lb and sparge twice.  With normal strength beers, a higher ratio like 1.75 qt/lb will hold onto the heat better like I just said.  There is nothing wrong at all about mashing down at 1.25 qt/lb – I did it for many years with great success.  Now I mash at 1.75 qt/lb for the improved heat retention.  But does it really matter?  No, not really, not a big deal.  There are far greater things in brewing worth more consideration than mash ratios.

+1.  I like the extra thermal resistance to temp change with a higher ratio, but that’s pretty much it.