What kind of equipment and what process are you using? My back-of-the-envelope figuring says you're getting about 60% efficiency. That's a skosh low, but not all that unusual. First thing I'd do is check the gaps in your mill and take a look at the crush.
Also, some unsolicited advice: 6 lbs is a lot of crystal. That's probably why your FG is relatively high despite a very low mash temperature. Basically, you want to limit specialty malts to no more that 20% of the grain bill. I'd cut the C60 at least in half and make up for it with some darker base malts like Vienna or Munich.