Question about substituting Crystal Malts

I am in the planning stages of brewing an oatmeal stout and the recipe calls for 1lb of 40L crystal malt which is 7% of the grain bill. The website I am ordering from and my local supply store are currently out of 40L and won't have it in stock for another couple weeks. So my question is since I am inpatient and don't want to wait to order the grain, should I order 20L or 60L as a substitute or should I just wait or buy it? If I go with 20L or 60L should I buy more or less than a pound or just keep it the same? I know that Crystal Malts differ mainly on color but I don't know how much of a flavor difference there is between 20, 40, and 60L.

 

I'd probably get a half pound of the 20&60 and call it even. No scientific data to back that up. But if I wanted 40 and couldn't get it that's what I would do. Figure the difference of the 2 should balance around 40 that's my .02 anyway.

 

Still pretty new to brewing, so please don't take this as gospel. Can't you use 1/2lb 20 and 1/2lb 60? That's what my LHBS recommended when I was trying to find a grain that they didn't have. That should suffice.

 

using 50:50 of 20L & 60L would get you in the ballpark for colour but the flavours would be different. As I have heard the lower crystal malts have more of a sweetness/honey flavour and going darker starts tending towards caramel then toffee flavours. So hypothetiacally the recipe might be going for a caramel flavour but the 50:50 mix ends up with a sweet toffee flavour.
What is the style you are brewing - in all honesty you could do any option: 1# 20L, or 1# 60L, or 50:50, or some other ratio and they would all make beer and you probably wouldn't bat an eyelid

 

^ this

The different crystal malts differ in both color an flavor. The darker the color the "richer" and more robust the flavor, with the darkest (120-150L) giving you raisin and prune and burnt caramel. Given your options I would probably go with either a 50:50 mix or all 60L. I don't think all 20L will give you the flavor you're looking for in this beer (nor the color).

 

Since you are doing a Stout recipe, where the color will be dark anyway, I would bump up and use all C-60 in place of the C-40. The taste should be a little more pronounced caramel than the C-40 version.

 

Haha, I missed the fact that it was for a stout. I agree with the last 2 posts, I'd just go all 60L

 

me too. i've had this idea and tried splitting the difference. i would say to just sub in whatever's close.