MTB

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I've done 9 extract batches and all of them were perfect. Today, I did my first PM and the OG was 1.052. It was supposed to be 1.065. Here's the process of my brew day:

1) Heated 2 gallons to 162* then added 5lbs of grains.
2) The temp dropped down to 153* then I wrapped the pot in a towel and blanket.
3) After an hour, the temp was 152*.
4) I heated 2gal of sparge water in another pot to 170*, then teabagged the grains in that for a few minutes then put the lid on and let it sit for a few more mins (the temp dropped to 159 during this).
5) Took the grains out, added the wort from the mash and started my boil.
6) Did everything like I usually do, then whirlfloc with 10 mins left and added 6lbs of LME at flameout.
7) Cooled the wort to 100* then added 1gal of ice that I froze last night.
8) Aerated the wort by transferring it from my primary to another bucket 6 times.
9) Took my gravity reading and was surprised to see it so low

What did I do wrong??

*notes: I did notice quite a bit of hop sediment in my graduated cylinder when I took the gravity reading

Walker

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I've never done a PM brew, but I think the "tea bagging" is probably not very effective at rinsing the sugars from the grains, so you might have left a lot behind.

How was the grain crushed? And what was it in?

That gravity is so low, it's coming up to like 25% efficiency, which is almost impossible.

__________________
Ground Fault Brewing Co.

MTB

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I followed this guide: http://www.homebrewtalk.com/f39/easy-partial-mash-brewing-pics-75231/

that's where I got the teabag idea from.

The kit is NB's RyePA and the grains were 3lbs Rahr 2-row, 1.5lbs Weyermann Rye malt, and 0.5lbs carared. They came crushed from NB.

I also just checked my hydrometer in distilled water and it read 1.000.

rebel80

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This. It sounds more to me like you're just steeping grains rather than doing a true partial mash. You're just not going to extract sugars doing it this way like you would from a true mash.

MTB

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How am I not doing a true partial mash? I followed the guide that has worked for many others

HomebrewMTB

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This ain't a tea party. You gotta squeeze it. Use a colander and a pot lid to get the goodness out. And stir it thoroughly during sparge. Then squeeze it again.

rebel80

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This would definitely extract the sugars, but conventional wisdom would tell you that this would lead to tannin extraction as well. That being siad, I've squeezed the hell out of plenty of grain bags when steeping specialty grains and never noticed any ill effects.

MTB

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I did stir and squeeze during the sparge. I just don't get how the OG got so damn low...

Rev2010

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I'm thinking it was the grain crush. My first AG hit my target OG. My second one, a hefeweizen, came in way low. Everybody suggested it was the crush and I emailed Northern Brewer and their response seemed to agree with it and an apology, but that is wheat which is a smaller kernel. I have a grain mill on the way now for my third AG batch.

Rev.

MTB

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Was your first AG from NB? What about the 2nd time around? I might have made mistakes during my first PM, but seriously.....I don't see how they could affect the OG by so much.