Excess Wort Question

[TheWitGuy]

I just finished my brew today and I noticed that I had about 2 gallons of excess wort and that's after filling a 6 gallon carboy. Luckily I had another carboy and dumped it in there. It's currently cooling in my basement before I pitch yeast, but is this normal?

Here's the recipe:
https://www.homebrewtalk.com/f12/3-floyds-zombie-dust-attempt-help-info-requested-245456/

I tweaked the hop amounts to keep the IBU's around 62~ and also added more base to increase ABV. What's wrong here?

 

[acidrain]

You must have had less boil-off than you thought, or sparged more than you needed.
What were your volumes, and what is your boil-off rate? What were your gravitys?

 

[TheWitGuy]

BeerSmith said OG to be at 1.064, long hold behold that's what I got. I just noticed that in the final copy of the recipe it says 7 gallons after boil. Wtf is going on here?

 

[DrunkleJon]

You just need to dial everything in. Did you set up your equipment manually in BS? What are your figures for trub loss chiller loss etc. I noticed the same problem and have been adjusting the equipment measures (boiloff, mash tun loss, trub loss, etc and am getting there.

7 Gallons? What is your batch size? 6.5 gallon with .5 gallons set as trub fermenter loss?