Larger Grain Bill & Problems hitting mash temp.

I've run into an issue in back to back brews where I've undershot my mash temp when brewing beers with a larger grain bill(1.070 - 1.088).

The first time I followed mashed in 2 degrees higher than the infusion guidelines on Beersmith called for (They said 160F I mashed in at 162F), on a 1.071 18lb IPA. I ended up undershooting my 149 target by and hitting 147.6.

Today I'm doing Denny's vanilla bourbon porter (1.088 22lb grainbill), which calls for a 155F sacc rest. Beersmith said to mash in at 165.8 and brewers friend suggested 167F. I mashed in at 168 and by the time I was done mixing the grain and making sure there was no dough balls (maybe 2 min from adding grain to done) I was at 150F, 5 full degrees short.

I mash in a 10gal round cooler and I believe beersmith calculates volumes based on 1.33qt/lb. Is this normal? Am I missing a process gotcha?

There are a bunch of factors that beersmith uses to calculate the strike temp. You can change the qt/lb ratio if you want. Grain temp and mash tun temp do make a difference in the resulting strike temp.

Do you preheat your mash tun?

Yeah, preheating the MLT is a must. I love Beersmith, but I despise the mash calculator. I use this site and I've never had a problem.

http://www.brewheads.com/batch.php

BryanJ said:

There are a bunch of factors that beersmith uses to calculate the strike temp. You can change the qt/lb ratio if you want. Grain temp and mash tun temp do make a difference in the resulting strike temp.

Do you preheat your mash tun?

Click to expand...

Yup, I sure did. I used to add 3 gal of 150ish water to the mash tun then dump it and add in my regular mash water. Lately I've been lazy and just heating my strike water 10deg over my dough in temp and then cover the mash tun for 10 minutes or so. Usually by then the temp has fallen to dough in temps so I start adding in my grain.

I even accurately input my grain temp into Beersmith.