Cooper's says ~0.5%? Is that about right? Is it possible to take another gravity reading after the beer is carbonated (or will carbonation affect it)?
Dextrose = ~46 ppppg and is 99% fermentable. Let's take 5oz in 5 gallons for an example:
(5oz/5gal)/16oz * 46 ppppg = 2.875 pts * 99% * 131/1000 = ~.373% ABV.
My online calculator shows about .4%.I was suprised by how much it actually adds.Carbonation will probably affect by the bubbles causing lift on the hydro.I'll try on my next brew with known fg and see what it shows.
Also it will change the SG. Best way to check it would be to bulk prime and check a sample.
Considering a pound of corn sugar is about .6% and .8% I would say very little.