storing grain

Scott: How can crushed take up more room? At any rate, I never buy crushed. I always mill my own grain because I read somewhere it keeps longer. I bought food grade poly containers at Smart & Final with resealable lids. Knock on wood, but I haven't had a rodent problem. Sometimes I have to leave poly bags of grain in a Coleman cooler until I have space in one of the containers. I would never leave a poly bag out in the open.

I know that it takes up more room, because I had an instance where I was going to use up an entire bag of grain on some very high gravity brews, so I had my LHBS crush it all.  It wouldn't all fit back into the original bag.  They had to get a grocery store sized paper bag and put the overflow into it.  I thought ahead while he was grinding and had him put 18 lbs. in the grocery store bag, which was enough for my first batch.  We could only roll the top of the original grain bag back down one turn, even though it only had 32 lbs. of crushed grain in it.

As far as how could it take up more space when it's crushed, I don't have an answer for that.  Maybe the fact that you now have many, many more particles causes there to be more air space between the grains than before.  But that is just a guess.