How should I adjust a recipe to match the FG of the style?

How should I adjust a recipe to match the FG of the style? I'm trying to make an Imperial IPA. It's an extract recipe with specialty grains that I came up with on my own. The style should have a FG between 1.010 and 1.020. My recipe ends up at 1.022. I'd love to get closer to 1.015. Here's the recipe so far:

FERMENTABLES:
1 lb - Caramel / Crystal 40L (9.09%)
1 lb - Cane Sugar (9.09%)
9 lb - Dry Malt Extract - Light (81.82%)

HOPS:
1.75 oz - Magnum (AA 15) for 60 min, Type: Pellet, Use: Boil
1 oz - Perle (AA 8.2) for 45 min, Type: Pellet, Use: Boil
1 oz - Cascade (AA 7) for 30 min, Type: Pellet, Use: Boil
1 oz - Cascade (AA 7) for 20 min, Type: Pellet, Use: Boil
1 oz - Perle (AA 8.2) for 15 min, Type: Pellet, Use: Boil
1 oz - Cascade (AA 7) for 10 min, Type: Pellet, Use: Boil
1 oz - Cascade (AA 7) for 5 min, Type: Pellet, Use: Boil
1 oz - Perle (AA 8.2) for 0 min, Type: Pellet, Use: Aroma
1 oz - Cascade (AA 7) for 0 min, Type: Pellet, Use: Aroma
1.5 oz - Cascade (AA 7), Type: Pellet, Use: Dry Hop
1.5 oz - Perle (AA 8.2), Type: Pellet, Use: Dry Hop

YEAST:
White Labs - Dry English Ale Yeast WLP007

Are you using software to get that "anticipated" FG? Software is notoriously bad at predicting final gravities. I'd recommend ignoring the predicted FGs, most of the time. Make sure the extract you buy is highly fermentable, treat your yeast right, and with 10% sugar, you should be fine.

Also, what is your OG? The higher the OG, the higher the FG, generally speaking. If you want something that finishes extra dry, up the percentage of sugar, or lower the OG, or both.

Since most of your fermentables are in the form of highly-attenuable sugars, I would err on the upper end of your yeast attenuation rate. I'd say set it at 79%. This recipe is assuming a 75% yeast attenuation.

Depending on the numbers you're using, your OG may be too high. At 79% attenuation this recipe would finish at 1.019 but still...

Cut your cane sugar to 0.5 lbs and, assuming you have 79% attenuation, you should finish out near 1.018. Your OG would be 1.087 which is a respectable number for an IIPA.

Good yeast health and proper pitching rates will help improve your attenuation. Are you making a yeast starter?

See mrmalty.com for a calculator to find the proper pitching rate.

Brewing software AFAIK doesn't take into consideration pitching rates or mash temps, which happen to be two extremely important factors in attenuation. If you mash somewhat low and pitch a big starter, you'll hit your desired FG. I use BrewTarget, which lists S-05 at 75% attenuation. I know off the top of my head I've gotten as high as 85% from the strain.

Thanks for the help. Sorry it's taken me awhile to respond.

Also, what is your OG? The higher the OG, the higher the FG, generally speaking. If you want something that finishes extra dry, up the percentage of sugar, or lower the OG, or both.

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My OG is 1.09 and I am using brewersfriend to calculate. I do want something that finishes up extra dry but I've also read there are limits to the percentage of the fermentables that should be sugar so I tried to limit it. I'm not even sure how a higher FG would affect the taste of the beer. I just know what is supposed to be "normal" for the style.

Cut your cane sugar to 0.5 lbs and, assuming you have 79% attenuation, you should finish out near 1.018. Your OG would be 1.087 which is a respectable number for an IIPA.

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LOL! I have gone round and round on the recipe proportions. I sure could cut the sugar. Would I still end up with an IIPA that has a clean dry finish?

Good yeast health and proper pitching rates will help improve your attenuation. Are you making a yeast starter?

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To be honest I was going to use Mr. Malty to determine how many vials to pitch without a starter- mainly due to laziness and lack of experience. I know it's supposed to be easy but I worry about contamination... I could do it though...

I use BrewTarget, which lists S-05 at 75% attenuation. I know off the top of my head I've gotten as high as 85% from the strain.

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I'm not mashing- just steeping some crystal but I did consider S-05. Again, I've gone back and forth on the yeast component of the recipe. I have good experiences with Safale in the past.

humulene said:

My OG is 1.09 and I am using brewersfriend to calculate.

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1090 is a big beer, make no mistake. Even if you use 9% simple sugar to get there, that still means there's a lot of malt. Check the data sheet for the extract you use. I mean something like this, which is the sheet for Briess's pilsner extract. It shows the degree of fermentability as 75%, which is the maximum you can reasonably expect to achieve. Choose an extract that gives you this level or higher. That allows you to compute your FG, provided everything else goes well.

For example, in this recipe (assuming 5.25 gallons), you're getting roughly 77 gravity points from the extract, 4 from the crystal, and 9 from the sugar (roughly). If your extract is 75% fermentable, and the crystal is roughly 50% fermentable (it'll be more than that, but I'm erring on the side of caution), then you can expect 19.25 points to remain from the extract and 2 from the crystal. That will leave you with an expected FG of 21.25 (sugar is 100% fermentable). If that seems high to you, drop the extract a bit. If your OG seems low, then add more sugar to get it back up. So the higher the percentage of sugar, the lower the expected FG. You can play with the ratios to get the OG and FG you want. I wouldn't go over 20% sugar by weight, at the absolute most. Naturally, if you change the recipe, you'll have to redo the numbers, but you should be able to follow the example above. It's pretty easy.

Everything from that point on depends upon yeast. Pitch enough, healthy yeast, and control fermentation temps well. Ideally, that would be pitching low and then holding steady or steadily increasing by a small amount.

The 9# of DME is made of of at least 1# of cara-pils. Thus, between the DME and C-40 you have 18% crystal malts (if you consider cara-pils a C-malt). Cut the C-40 out or use a 1/4 oz of darker stuff if it's in there for color. Should help...