Boy, 50 IBU seems kinda on the low side for an Am. BW. I think the last one I did was around 130!You're right Denny, I checked my notes and it was actually about 75 IBU bittering addition, 90 IBU total. IIIRC you age them for a lot longer though, right? A year or more?
Will a hi OG beer still finish with a low FG.With all-grain, you're in good shape because you can mash low and produce a very fermentable wort. I've mashed my BWs at 149°F for 90 minutes. Combined with an attenuative yeast like Chico (US-05/1056/001), 80-85% attenuation is common.