Potential Dumb Grain Question

[nstowe81]

I've recently stopped buying All-grain kits and started buying grains from the LHBS. First beer was Denny's Rye IPA, hit my numbers everything was fine and dandy. (must have been beginners luck) This latest brew was a Winter Warmer with British 2-row (pearl) as the base malt, marris-otter was sold out.
My pre-boil gravity was super low (and yes I accounted for temp). I immediately start trouble-shooting. When cleaning out the MT I noticed not all the grains were crushed properly Which would account for the efficiency problem. Lastly, I used the same mill at the LHBS with the same gap setting. So here's the question, are British Malts smaller than US Malts resulting in a bad crush?

 

[stpug]

Some malts are smaller grained than others. Maris otter is generally plumper than standard US 2row so you actually get a little better efficiency from it. Dingemans pilsner is a little less plump than us 2row but it's doesn't seem to affect efficiency on my system by much, if any. Carapils is considerably thinner than us 2row and could use a double crush, but not necessary since it's more a specialty grain. And us 6row is MUCH thinner than us 2row and should be double-crushed; I had close to 10% efficiency hit using some 6row due to poor crush. At least this is what I've observed from the grains I buy from my LHBS.

 

[nstowe81]

I guess a double crush policy is in order when purchasing grains.

 

[stpug]

I figure as long as you're getting a decent efficiency and it's consistent, then just modify your recipes to account for it. I get a pretty consistent 74% efficiency from my LHBS with most all grains EXCEPT 6row, and I'm happy with that. I would probably be okay with down to about 70% as long as it's consistent. I've started using a new mill I bought with a slightly tighter gap setting than my LHBS and my efficiency went up to about 78-79% on the last couple batches, BUT the sparging has been compacting a little more also. So in the end, it's usually a tradeoff.

 

[branman]

Thanks for the info stpug. Just got my own mill myself and I was getting 74-76% and proud to say I touched on 80 once. But since I got this monster mill I hit 70%. Think it would be best to shorten the gap or double crush? I would like to get back to where I was

 

[stpug]

I would opt for tightening the gap a very little bit - that should get you where you want to be without pulverizing it too much. A slightly tighter gap and a slow grind should give good crush without totally destroying the husks. When mine arrived the thumb set screws were loose and the gap was visually not parallel so I had to set it to an unknown gap using what I had on hand (some calipers and post-its). I guessed that my gap was around .030" which is slightly tighter than how it would have been shipped (.037-.045"), but now that IslandLizard mentioned using a credit card in another thread I need to recheck the gap so I'm a bit more confident about what I'm actually milling at.

 

[branman]

Thanx, I will check it with a credit card myself. I'm almost sure that the gap is wider than a card.. should it fit loosely or kind of snug?

 

[stpug]

Here's the post from ___ talking about using a credit card to help set the gap:
https://www.homebrewtalk.com/f36/effect-mill-size-433421/index2.html#post5534011

It was actually IslandLizard who posted it.

 

[branman]

Good read thanks again...