Fining agents

If it's a flavor issue, then as Jack did a great job explaining, it probably isn't tannin astringency at all.

Again, depending on what style of beer you are making, this might just be a matter of too high an IBU level to begin with for your palate. Have you ever had Hill Farmstead Edward? That's an 85 ibu pale ale. If you've had it and don't mind the bitterness, then it's pretty easy to rule out the idea that you are simply making your beer too bitter for your palate.

I believe "long lingering hop bitter finish" is a condition that has received some research but may not be definitively figured out yet. Some argue that using large amounts of hops that are high in cohumulone can cause this effect. I believe others have claimed water chemistry might be the driving force. Not claiming that either one of those theories have been proven though.

 

So then, like I said, we can rule that possibility out. Moving onto the astringency vs bitter finish concept....
Is it a dry puckering mouth feel issue or a long lingering displeasing bitter taste you are experiencing?

 

If he's adding 3 oz of something in the range of 16% AAs, that's a calculated ~ 150 IBUS. Pretty much maxing out bitterness. Take that down to 1 oz. Might change the entire character of the beer.

 

I didn't double check by hand, but I originally said roughly 80 ibu's because beersmith gives me the following:

5g batch size
1.063 OG (middle of the IPA range)
3oz ctz (15.5 aa) @60
brewhouse efficiency 75%

IBU = 81.1

 

I just checked BrewCipher and got 146 using standard tinseth and 79 using @VikeMan's modified tinseth. 3oz still seems a bit high to me if the OP is concerned about high bitterness to the point of astringency. I'd advise backing that down a bit.

 

Assuming 1.070 OG, 60 min boil, and rounding AA to 16, I get roughly 126 IBUs. For 3 oz of 16 AA hops, 81 seems kind of low.

 

Sorry guys I just realized when I created a new recipe in beersmith for this "quick answer" it defaulted to an equipment profile that skewed the figures. Using an equipment profile designed for a 5 gallon all grain batch, beersmith gave 146 IBU's for 3oz of columbus at 60m in a 1.063 OG brew w/ 75% brewhouse using tinseth.

I also did the math by hand and proved 3oz definitely wouldn't result in 81 ibu's like I previously posted. Actually it would be less than 32 grams of columbus for that ibu target (assuming 28% hop utilization which is a figure we used in an example in brew school although it seems higher than what beersmith assumes)...

Lb hops = (bbl beer) x (IBU target) / (% alpha acid) x (% utilization) x 3868
Lb hops = 0.16 x 81 / 0.155 x 0.28 x 3868
Lb hops = 12.96 / 167.87
Lb hops = 0.07

0.07 bbl = 31.36 grams of 15.5% aa hops for 81 ibu's (beersmith claims 44g or so based on the defaults in my copy)


NOTE: Beersmith (with a more "in line" equipment profile) suggests using 1 - 1.5oz of columbus at 60m to get the ibu's into a typical IPA range. So, either way, the OP is either using 2x as much (as the high end of the IPA range) or close to 3x as much (on the low end of the IPA range) bittering hops as a BJCP style range would call for.

 

Sorry again that last formula line should read 0.07 lb hops = 31.36 grams

 

And actually 0.07 lb = 31.75 grams to be precise