1st Batch Sparge; Low Gravity

I did my first batch sparge yesterday and, while the procedure went well, I felt that I might have done something wrong. My efficiency was very low and ended up with a lower than expected OG. Here’s a quick step by step:

12 - lbs pilsen 2 row
2 - lbs white wheat
1/2 - lbs munich
1/2 - flaked oats

4.7 gallons of water @172 degrees stabilized mash @152 for 70 minutes.
Drain first runnings.
4 gallons of water @185 degrees for mash-out @168 for 10 minutes.
Drain second runnings.
Collected 7.25 gallons in kettle.
add 1 - lbs honey.
Boil for 65 minutes, chill.
collected 5.25 gallons.
Original gravity was 1.070.

I thought I would be more around 1.078 with 15 pounds of grain and 1 pound of honey. Where did I go wrong? Or is that to be expected with batch sparging?

Thanks!
-Mike

In cases of low efficiency, the first thing to look at is the crush. especially using wheat, which has smaller kernels than barley and sometimes doesn’t get well crushed.

Thanks, Denny!
It was my first batch sparge; do you think 64% efficiency is horrible for batch sparging? Am I way off?

Thanks!
-Mike

Thanks, Denny!
It was my first batch sparge; do you think 64% efficiency is horrible for batch sparging? Am I way off?

Thanks!
-Mike[/quote]

That’s about where I started. After tweaking my crush, equipment and technique I’m now at about 85%. So take good notes and stick with it!

Considering the differences we have in whether we leave break behind and if so what volume it is, I like to check my mash based on preboil gravity and volume. In fact, you can get a good idea just based on first runnings gravity.

After crush, another big one is dead space in your tun. Drain every bit of liquid you can, I tip mine on its edge and let it drain out as much as possible even before the sparge.

This may sound too simple, but try stirring more after you add the water. I remember when I started all grain (and batch sparging) my efficiency was on the low side. It went up noticeably after I starting stirring the hell out of my mash.