[SPAMR]

In the past I've used 5 oz. of priming sugar to bottle condition my ~5 gal. post-boil brew, but that was a recommendation based on the kit I was using.

I brewed my first all grain, custom recipe batch a couple of weeks ago and I will be bottling tomorrow.

The OG was 1.060. Beer Smith is recommending 3.8 oz of corn sugar which seems low. The only other thing to note is that the trub / dry hopping has definitely diminished some of the total batch size. If I had to guess I would say its down to ~4.5 gal. I suppose this is something I should measure once it's in the bottling bucket!

Any advice on how much priming sugar to use?

[Stevie]

I'd target 2.5-2.7 volumes. Beersmith will be able to calculate the amount needed based on your final volume. Temperature needed in the calculator is the highest temp the beer was fermented at and is used to determine the amount of residual co2 in solution from fermentation.

4.5 gallons at 2.6 volumes at 72° would need about 4.25 ounces

[SPAMR]

I'd target 2.5-2.7 volumes. Beersmith will be able to calculate the amount needed based on your final volume. Temperature needed in the calculator is the highest temp the beer was fermented at and is used to determine the amount of residual co2 in solution from fermentation.

4.5 gallons at 2.6 volumes at 72° would need about 4.25 ounces

Just added this to Beer Smith, thank you!

Out of curiosity, what is the margin of error for exploding caps, etc. due to over carbonation? 

[klickitat jim]

It's not just a matter of how much sugar for what volume of beer, but also what the highest temp the fully fermented beer reached.

[SPAMR]

It's not just a matter of how much sugar for what volume of beer, but also what the highest temp the fully fermented beer reached.

I would say 72* since it was hotter over the past few days (in NY). The average was 65-68*.

How much of a role does the temperature play?

[Stevie]

I'd target 2.5-2.7 volumes. Beersmith will be able to calculate the amount needed based on your final volume. Temperature needed in the calculator is the highest temp the beer was fermented at and is used to determine the amount of residual co2 in solution from fermentation.

4.5 gallons at 2.6 volumes at 72° would need about 4.25 ounces

Just added this to Beer Smith, thank you!

Out of curiosity, what is the margin of error for exploding caps, etc. due to over carbonation? 

It's not the caps, but the glass you need to worry about. I've heard and read many different numbers, but I like to stay below 3 volumes, maybe 3.2.

[klickitat jim]

It's not just a matter of how much sugar for what volume of beer, but also what the highest temp the fully fermented beer reached.

I would say 72* since it was hotter over the past few days (in NY). The average was 65-68*.

How much of a role does the temperature play?

I don't use beersmith but I imagine his carbonation calculator asks for beer temp. When you see that, it's asking for highest temp the beer got to AFTER fermentation was completed.

I use brewers friend.
5 gallons 2.5 volumes 60F needs 4.4 oz corn sugar
5 gallons 2.5 volumes 70F needs 4.9 oz corn sugar
If it got up to 80F it needs 5.2 oz

So it's not huge, but some difference. This is another benefit of temp control. When I bottle condition I know for sure what the temp was.

Something you can do is enter the least volumes you want at the low estimated temp and the most you want if it were hotter then prime with a number between those two. Like maybe min of 2.25 max of 2.7 and then maybe the average of those two sugar amounts is 4.5 oz for 5 gallons.

You are right though, earlier when you mentioned not doing your sugar calculation until you know how much is in the bottling bucket.

In the end I'll tell you the most common mistake. Not beings patient and ensuring that the beer is all done fermenting. Lots of people see the airlock quit, take a reading and it shows what the recipe suggests, so they bottle it up. But the beer still had some work to do and they end up with foam rockets.

[dilluh98]

I'd target 2.5-2.7 volumes. Beersmith will be able to calculate the amount needed based on your final volume. Temperature needed in the calculator is the highest temp the beer was fermented at and is used to determine the amount of residual co2 in solution from fermentation.

4.5 gallons at 2.6 volumes at 72° would need about 4.25 ounces

Just added this to Beer Smith, thank you!

Out of curiosity, what is the margin of error for exploding caps, etc. due to over carbonation? 

It's not the caps, but the glass you need to worry about. I've heard and read many different numbers, but I like to stay below 3 volumes, maybe 3.2.

I've done 3.5 volumes in standard 12 oz and 22 oz several times with no issue. Unless there's a defect in the glass, I would guess one could go even higher but I don't. The only exploded bottle I've ever had was due to an infection - not much you can do about that other than up your bottling sanitation game.