Water Levels and Low OG

I've been an exclusive extract brewer for the last couple months, and I am consistently low on OG. I know, this has been a common lament, and I've tweaked some variables that have improved my OG some. I've calibrated my hydrometer, tried my best to dial in on my H20 volumes, and I enter all ingredients into Beersmith2. As many have pointed out, Beersmith is consistently calculating a lower OG than the Brewers Best Kits that I use. However, I'm still coming in under the estimated OG of Beersmith. My last two BB kits were:

Munich Helles, Est. OG: 1.041 Actual OG: 1.038
Summer Ale, Est. OG: 1.40 Actual OG: 1.038

I've also pieced together my own extract recipes using Beersmith2:

American Wheat Est. OG: 1.048 Actual OG: 1.042
Maple Pecan Porter: Est. OG: 1.062 Actual OG: 1.057
American Pale Ale: Est. OG: 1.056 Actual OG: 1.048*

The only thing I do differently from the instructions is that I always do a full boil. I also steep my specialty grains in the full volume of water (usually 6.75 gallons). I aim for 5 gallons in my corny keg after all evaporation, cooling shrinkage, trub loss, etc). Some of my OG numbers are pretty close, but I'm trying to get as exact as possible with my brewing system before I move to all grain.

Is it possible that steeping my specialty grain in a full volume is causing the lower OG?

If not, the only variable I can think to adjust is my volume, but I've been using Beersmith to calculate the volumes. Do most people hit their numbers with Beersmith's measured volumes?

Note* The american pale ale I brewed was on a new kettle. SO even more possibility that volume is the problem since it was the first time using this kettle. Although I did run a test run to measure evaporation rate.

All the est. OG above are from Beersmith2 and not the kit instructions.

While its possible that the extracts you're buying are slightly lower gravity than the presets in your software, it's doubtful.

You're on he right track, most missed gravities on extract are a measuring error such as measuring when the wort is not well mixed. when measuring, are you getting a good homogeneous sample at the temperature for which your hydro is calibrated? Using your software's hydro correction formulas will also account for this. On that note, how confident are you in your thermometer? Makes a big difference sometimes.

Just a thought... Good luck with your beers!

Sounds like you are using a lot of water. Maybe just try to cut it back some? Your numbers are fairly close so you could really just relax and enjoy it.

Just one more thought though, what temp is wort when you measure og? Remember heat thins the viscosity of any liquid and most hydrometers are calibrated for 65F.

definitely have a homogenous mixture since I'm doing full boils (no water top off). My thermometer is the highly touted thermapen, and I've calibrated my 60 Degree hydrometer with distilled water. I always chill my samples to 60 when taking a hydro reading.

I've been thinking about this one while reviewing John Palmers book. The software you are using assumes a certain percentage of overall efficiency. I think what you should try for your next recipe is determine your max efficiency the divide that into what gravity you actually get and find your own percentage. Then keep that number in mind when you design future recipes. Hope that helps.

I didn't mean to chase you off. If I did? I can help with the numbers if you have a recipe. I just really think the best way to solve this is by adjusting your efficiency expectations.

The only thing I do differently from the instructions is that I always do a full boil. I also steep my specialty grains in the full volume of water (usually 6.75 gallons). I aim for 5 gallons in my corny keg after all evaporation, cooling shrinkage, trub loss, etc). Some of my OG numbers are pretty close, but I'm trying to get as exact as possible with my brewing system before I move to all grain.

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I think that is your problem. You need to aim for 5 gallons in the fermenter to come out at the right OG. If I were you I would start at 5 gallons plus your boil-off. For example I would use 6 gallons since I boil off one gallon in an hour.

I personally would rather have to top of just a touch to hit my 5 gallon volume in the fermenter - this solves the too much water possibility. Also, I strain my wort into the fermenter. Its worth the time to me to get every last drop of sugary goodness.

That having been said, I've entered recipies into beersmith and came up with numbers other than what the recipe states. Might have to do with your settings. When I used to do a lot of kits (many from NB) rarely was my OG off from what the kit maker stated if my volume was correct. FG varied based on fermenting conditions.

If you've got a good bathroom scale, you can get a pretty decent estimate if your volumes are off. If you assume the density of water is 8.33 lbs/gal, then if you multiple that by the OG and have a scale accurate to with say 1lb you can estimate the volume to within ~0.1-0.15gals. If your OGs are off just due to volume, then for most of the OGs you listed above your volume would have to be off 0.2-0.5gals.