I made a Gluten Free Pale Ale last night. It has 6lb sorghum syrup, 1lb Sucanat sugar full boil (2 1/2 gallon water). Then 2 1/2oz of cascade pellet hops spaced out in the boil. I also added 1/2tsp irish moss in the last 10 min. The starting gravity was 1.040, supposed to be 1.050, is that bad? 1st time trying Gluten Free.
Steve
I'm confused, you say you did a full boil, but then say 2.5 gallons of water.
Did you actually 6 lbs of sorghum into a 2.5 gallon batch?
I'm going to assume you meant something else (otherwise your OG should have been like 1.1, which would be huge).
Beyond that, when you are using extract, there are a couple reasons you wouldn't hit your target OG:
1) The target OG you calculated was incorrect (math error, incorrect amounts of extracts, etc) for the ingredients intended
2) You didn't use the ingredients intended (you measured your extract wrong and only used 5 lbs, or you added extra water and ended up with 6 gallons in the fermenter)
Since the target OG you listed matches up closely with what I got from an online calculator, I'm guessing that isn't the issue. Number 2 seems possible.
However, there are also several ways you can hit your target OG, but get a different reading:
1) Inadequate mixing of wort with top-off water, as someone already mentioned
2) Inaccurate reading. There are plenty of things that could throw off your hydrometer reading. An inaccurate hydrometer, bubbles, chunks of stuff floating in the sample...hydrometer sticking to the side of the test jar...just plain reading it wrong...incorrect temperature correction...