Took OG before adding last G of chilled water...

[azlane]

So, I jumped the gun and pulled my OG sample prior to adding the last gallon of water to reach 5G. Is there some way to calc what my OG would have been if I was at 1.076 for 4 gallons?

The ESB recipe I used as my base did not have specialty grains (I steeped .5 lbs each of munich and carastan grain) so I expected my OG might be a bit higher, but realized I screwed up when it was way high.

Thanks
Drew

 

[DocScott]

Sure:
OG=GU/V
76=GU/4
GU=304

Then recalculate to get OG with 5 gallons
OG=304/5
OG=60.8
OG of 5 gallons equals 1.0608

This is assuming you calibrated your original reading for temperature.

 

[GotDrunkThenLost]

I pulled this formula into excel after finding the formula somewhere on here

=(((Postboilvolume*((original_gravity_pretopoff-1)*1000)/posttopoffvolume))+1000)/1000

So in your case I'd guess at your gravity being in the region of 1.061

Edit:
Ha Ha, looks like DocScott and me just validated each others working .

 

[azlane]

Fantastic, this is just what I needed.

Yes, I took my reading at 75 degrees so I think I am good!

Thanks so much.

 

[kh54s10]

How long has it been? If fermentation has not started you could just take another reading.

Otherwise: use the calculations given.