Need efficiency help

So I have done 2 Partial Mashes and I am not what I want out of the efficiency. I am about .010 - .030 points off on my pre boil gravity. I have relied on Beersmith for my volumes and I think that may be my problem. I used Beersmith's suggestions on water volumes. I do not think the problem was my crush as I compared to many pictures here on HBT and it looked similar.

I use a 5 gallon cooler with a paint strainer bag and I do a full boil a little over 7 gallons too account for cooling and trub loss. My temp was consistent at 152F for about 45 min then dropped to 150F which I don't think is a problem. Both batches I have used 10 lbs of grain as suggested by many posters to use as much grain as possible.

I mashed in with 12.5 Qts using the 1.25 Qts per pound of grain. Beersmith suggested to use over 5.23 gallons for sparge in order to get to my Boil volume. Without thinking I did this, and I think it totally watered down my gravity.

Is my assumption correct? What other problems do you see? Should I decrease my Grain Bill?

Is your og off by the same margins?

Do you have more room in your mash tun for a larger(thinner) mash-in?

What was your pre-boil volume?

Who is crushing your grains? Most LHBS provide nothing more than an average at best crush, typically more course than desired to prevent stuck sparges or they simply don't adjust their mill frequently enough.

Next time ask them to run the grain through twice or tighten and adjust their mill, or better yet, get your own mill if you plan on doing AG moving forward...........

It is possible to use too much grain. There is a point where you actually get less sugar from more grain because it is tied up in grain absorption.

For details see here:
http://woodlandbrew.blogspot.com/2012/12/when-more-grain-doesnt-add-more-sugar.html

Have you adjusted the numbers in the equipment settings to match what your actual equipment?

I crush my own grain, I use a Corona mill.

I do have additional room in my mash tun. I would say about another gallon. Does using the bag bag hinder the grains from getting to the water?

My pre-boil volumes were 1.040 on my first attempt and 1.030 on my second. Expected was 1.050 for both.

Ideally the bag should be the same shape as the mash tun. That way you can stir it to get out all the dough balls and it will maximize the grain to water contact.

like this:
http://woodlandbrew.blogspot.com/2012/09/biab.html

This might be a better image:
http://woodlandbrew.blogspot.com/2013/01/hitting-exact-original-gravity.html

Have you considered converting the cooler so you can get away from BIAB? Mashing and lautering in a converted cooler is effortless aside from heating and pouring water.

JDFlow said:

Have you considered converting the cooler so you can get away from BIAB? Mashing and lautering in a converted cooler is effortless aside from heating and pouring water.

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Yes I have. I will probably do that here pretty soon but I just spent a lot of money on updated brewing equipment and SWMBO said I need to wait a few months.

JDFlow said:

Have you adjusted the numbers in the equipment settings to match what your actual equipment?

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I have tried but there is always a problem with the numbers. I have been using the "Single Infusion" Mash in and Mash Out.

histo320 said:

I crush my own grain, I use a Corona mill.

I do have additional room in my mash tun. I would say about another gallon. Does using the bag bag hinder the grains from getting to the water?

My pre-boil volumes were 1.040 on my first attempt and 1.030 on my second. Expected was 1.050 for both.

Click to expand...

Something that helped my BIAB efficiency was the advice to crush to the texture of coarse cornmeal -- much more than the usual crush. Also, I learned to be really careful about my mash temps, which tended to drift down quickly.

Also, started using one of these: http://ecx.images-amazon.com/images/I/21erH+vFQXL._SL500_SS500_.jpg to literally "mash in."

I spent about 2 or 3 minutes stirring and mixing the grain and water before I tied off the bag.

Looking back would using too much sparge water cause the low gravity?

I have changed my settings in Beersmith.

I am now going to use the Single Infusion w/ Batch Sparge.

It says a 4 step Sparge (Drain Mash Tun 1.83g, 1.83g, 1.83 g @ 168F). How long do I let each Sparge rest? Would it hurt my efficiency to add all water at once?

I know some people dunk sparge with BIAB, but it's not really that necessary. I definitely wouldn't do three sparges. When you say "tie off the bag," do you mean after you first mash in? I clip the bag to the sides of the kettle, and stir it up a couple times while the mash is going on. I would avoid bunching up all the grains, and try to keep liquid circulating freely.

+1 to allowing the grains to circulate.

Yes, adding all the water at once will hurt your efficiency, but even though it will be lower it will be at least 70% in most cases.