First AG in progress, SG low, Keep boiling?

I am in the middle of my first AG batch. I missed my starting gravity by a long shot, what should I do now?

Recipe:
12lbs 2 row Rahr
8oz White Wheat
8oz Carapils
12oz Crystal 15L

Batch sparged Mash 152 degrees for 60 min. First runnings were 2.8 gal 1.070. Second runnings were 3.9 gal 1.020. Pre-boil gravity 1.040. Was shooting for 1.052 based on Beer Smith.

Should I just go with it and boil for 60 min.
-or-

Boil longer to try to get to post boil 1.058? If I boil longer, approximately how many gallons would be left? Started with 6.7 gal.

 

My first AG last week, the mash OG was 1.039, was supposed to be 1.058. I boiled 90 min vs 60 and the the wort OG came in right on target at 1.071. Not sure if that was the right thing to do but it got the gravity up. We'll see how the beer turns out.

 

I'm about 5 gallons in the fermenter vs 5.75 like Beersmith predicted. Oh well, if the beer is good I'm fine with it. I have a lot of dialing in to do to get my AG's more predictable.

 

Yea, it would have been great to hit my numbers on the first try. I have a lot of dialing in to do. The volumes came out on target. I guess I should just relax and have a homebrew.

 

When in doubt, do this /\/\/\

 

You should be close after a 1hr boil not sure what your boil off rate is but it will be a least a gallon which should put you close to 1.052 maybe a few points off, you could add some DME also to bring it up. When you batched sparged did you stir at all I have never batch sparged so I don't really know if you are supposed to but I would think it would help with efficiency.

 

Nevermind, re read your original post. 1.058 post boil.

 

I stired twice in the hour.

 

I ended up boiling for 40 min. before my first hop addition (60min). Ended up with 5 gal into fermenter instead of the planned 5.5 gal and the final gravity was 1.050 versus the planned 1.058.

I forgot to aerate the wort last night (one to many homebrews) but I remembered and shook the heck out of it this morning (9 hr later). I am using Safale-05 and hydrated ahead of time so hopefully that mistake will not have too big of an impact. Waiting for the bubbling to start.

Now to start figuring out why I missed my gravity by so much. I hit my temps dead on thanks to beer smith. I keep reading that one of the biggest factors is crush. I honestly do not know what good crush looks like. I ordered the grains from MB already milled. Anyone every had a problem the MB crush. I see a MM 2.0 in my future but would like to invest in a draft tower for my kegerator project first.