Help me find my error(s) please.

[Queenster]

Hey guys,
In my first AG batch today my OG was a bit lower than I expected and I am looking for help in finding why. I am pretty sure it is just that my efficiency was low, but if any of you can help I would appreciate it.

How the day went:
Recipe: 13 lb 6 row, 1 lb 40 crystal, 0.5 lb carapils plus the bitter buddies and some irish moss
I was shooting for a low end imperial IPA
I mashed with 3.5 gal in a 5 gallon cooler and temps ranged from 151-154 throughout the 60 min.
I sparged with another 3.5-4 gallons and got to a 5.5 gallon boil.
Boiled 75 min with hop additions.
Added 1/4 cup table sugar at flame out (I know it is not great, but I didnt have corn sugar and I needed a little boost)
After topping off the wort I end up with a 6 gallon batch (I didnt realize how much my pot held and over filled a little)
I pitched Safale 05 and am waiting for some lock popping to start.
My OG was 1.043. I tested my hydrometer and it was .002 off so I could say 1.045, but still much lower than I needed for this one.
Can some of you brew vets point out all my mistakes here so I can improve my efficiency? Thanks in advance.

 

[Ozarks Mountain Brewery]

to get better efficiency, 3 things, crush finer and mash longer, or recirculate with a pump

 

[Nosybear]

If your error was 0.002, do nothing. That's measurement error on my hydrometer! One other note: There's nothing wrong with table sugar in a beer - in fact if you use Candi Syrup or sugar, you're using sucrose, which is nothing other than table sugar. Corn sugar is glucose, which is crack cocaine to yeast - in fact, don't add it until fermentation is underway or you may end up with fat, fed, happy yeast and underattenuated beer! And you'll never notice 1/4 cup of it in 5 gallons of beer.

My new mantra hangs over the brewery door at the Dry Dock Brewery in Aurora, CO: If it's not necessary, it's unnecessary. The longer I brew, the simpler my grain bills become.

 

[newmanwell]

Mash pH could be an issue. Happens in many pale beers depending on source water. There is ALOT of reading out there for water/mash chemistry.

 

[Nosybear]

I misunderstood your question: What was your target OG?