Another Efficiency Issue

[Whatsgoodmiley]

My first brew all-grain batch was a few days ago. 9 lb. pale ale malt and 1 lb. Vienna. My efficiency was somewhere between 70-75%. I just finished brewing my IPA tonight. It was 10 lb. pale ale malt, 1 lb. honey malt, and 1 lb. golden naked oats and I just measured the OG of my 5 gallons of wort to be 1.050... That's a 61% efficiency. The pre oil SG of my 8.06 gallons of prevail wort was 1.041! Assuming my volume measurements and my gravity readings are correct, what could have happened?

Edit: I forgot to add that the efficiency of my SG was looking to be 76%!

 

[day_trippr]

Pre-boil of 8.06g @ 1.041 to a post-boil of 5g @ 1.051 does not compute.
If the volumes and pre-boil SG check are accurate, the post-boil SG should be 1.066.

Something broke...

Cheers!

 

[Whatsgoodmiley]

Both readings were at room temperature

 

[Whatsgoodmiley]

Pre-boil of 8.06g @ 1.041 to a post-boil of 5g @ 1.051 does not compute.

If the volumes and pre-boil SG check are accurate, the post-boil SG should be 1.066.



Something broke...



Cheers!

Yeah that's what has me questioning my sanity

 

[day_trippr]

Well, presumably it's not a sanity issue, but there's no escaping the reality that at least one of those four measurements was erroneous...

Cheers!

 

[pricelessbrewing]

What they said. Need to be a bit more careful with your measurements.

 

[Whatsgoodmiley]

I thought I was careful. I measured both volumes in 2 quart increments using a measuring glass for cooking. I'm going to check my hydrometers against each other and against some sugar waters of known density when I get some time in a couple of days. If that's not it, I'll just need to be extra careful!

 

[jddevinn]

When did you take your preboil? Did you pull from the bottom or the top of the BK? Was it mixed well? Wort always ends up satisfying after sparging before the boil starts.

 

[Whatsgoodmiley]

It had definitely settled out, with the cloudier layer on bottom. And I took it from the top of the BK. I don't recall mixing it before taking the sample

 

[acidrain]

How do you measure water to the 100th of a gallon?

 

[Whatsgoodmiley]

How do you measure water to the 100th of a gallon?

You add 1 cup of wort to 8 gallons of wort.

 

[jddevinn]

Be careful.... kitchen measuring utensils are often WAY off. Calibrating with weight is a good idea.

That said I'm assuming you measured with the same instrument both times so calibration should be a non issue.

 

[Whatsgoodmiley]

I didn't know what else to use. I was hoping I was making accurate measurements when I sharpied up all my buckets with measurements form the measuring glass. Here's to hoping still!