I started brewing about a year ago, currently on my sixth batch, all using extract and some additional grains. My problem is that my beers consistently finish with a higher than expected final gravity. For the life of me, I can't figure out what I'm doing wrong.
My latest batch is the biggest failure yet. I don't think I can bottle it like it is. I modified the all-grain recipe linked below to use extract for the base malt. I did a "mini-mash" with the other grains (crystal, chocolate, smoked, black patent). The temperature at the end of the mash was 150F. I substituted 6 lbs. pale LME and 10 oz. pale DME for the base malt. I upped the second hop addition to a full 1 oz.
I plugged this recipe into Brew Target. It said my OG should be ~1.046 and my FG should be ~1.013. My OG was right on target when I pitched the yeast. I pitched one packet of hydrated Nottingham yeast at 74F. The airlock started bubbling within a few hours, went strong for about a day, and then just stopped. After 10 days, the gravity was 1.022. The taste is rather bland, not particularly sweet or bitter or ... anything else, really.
I used tap water from the filtered dispenser on my refrigerator. I aerated by shaking vigorously in the fermenter for a few minutes before pitching the yeast. Fermentation temperature is a consistent 68F.
I asked the proprietor at my LHBS for help. He gave me some yeast energizer and high attenuating ale yeast to try to get it going again. I gently stirred in the energizer and sprinkled the yeast on top. That was about 18 hours ago, and it shows zero activity right now.
Imperial IPA, OG 1.094, expected FG 1.023, actual FG 1.028
Pale Ale, OG 1.052, expected FG 1.013, actual FG 1.018
These things start out with the right OG, but they just stop fermenting and refuse to go any further.
Does anyone have any idea what might be wrong? What I might be doing to encounter this repeatedly? What I can do to salvage my latest batch?