Lovely job on filling out the BIABacus Ben 
. All is correct.great 
.
joshua wrote:
Maybe, since it is Late here, for me, I have Probably Missed something.
Sorry mate, I'm a bit lost on your maths there Josh 
. One thing though, rolled oats are fermentable and crystal grains aren't as fermentable but they still add to OG if that makes sense but...
joshua wrote:
... your Data does not match BIABACUS...
I think this second batch shows that there is a problem somewhere and we certainly need to start searching a little deeper.
mally's focussing on point #10 in the post he linked is excellent advice especially as I believe in England that some home brew shops pre-crush their malts a long time before they sell it. A couple of guys have said they have never had a problem with this but you'd really want to make sure that they store it dry. For example, typical malt has about 4% moisture content. I won't go into the maths but if this rose to say 10%, your efficiency into boil would drop by about 6%. Long-term storage of crushed grain may also lead to the eating of the 'sugars' by weevils or other organisms which again would reduce what you could expect from the malt.
The other one which I think would be worth checking at this stage is the pH of your water. Use the pH strips mentioned here. (Also check locally to make sure that there is nothing really obviously wrong with your water.)
I'm still not happy with your thermometers. What they measure at freezing and boiling point is not relevant. They need to measure the same at mash temp. See if you can buy a third cheap thermometer, heat some water up to just above scalding (leave your finger in until it starts to go red ) and then see how the three thermometers compare.
I'd be very hopeful that doing the three things above will identify the problem.
PP
Statistics: Posted by PistolPatch — Tue Oct 07, 2014 4:51 pm