Brewing sat with a friend and it’s my first attempt at a 10% abv beer. Have about 18.5 lbs of grain. I’ve read a lot of different methods on how to mash and sparge a beer of this size. Looking for some pointers before sat to help hit the desired OG. Thanks
Can you explain your equipment? If we know what your gear is like we can give you better advice.
Plan for a lower than expected pre-boil gravity and keep some DME on hand.
MY mash tun is a chest cooler, my buddy has a pot with a screen but he’s reluctant to use it to mash in. (afarid of scorching the grains). Typically fly sparge. My efficiency with my cooler tends to be around 72-75. Have lots of big pots and burners. Not sure what set up we will use. It’s his brew really I may try to talk him into mashing in his pot but unsure if he will want to.
What style of beer are you brewing? It may be helpful to mash low and add a small % of basic table sugar to ensure your FG isn’t too high. Plan for 5-10% lower efficiency if not more…
A Russian imperial stout, I told him to have some DME on hand, he wants it to be an imperial pumpkin for next fall, i suggested molasses as another possibility.
Don’t use very much molasses. A little goes a long way. The flavor is very strong, even in dark beers.
What yeast strain are you using? Can you post your recipe detail?
14 lbs of marris otter
1 lb biscut
1 lb of crystal 60
1 lb of chocolate malt
1 lb of special b
1/4 lb of black patent
1/4 lb of roasted barley
using Belgium abbey 2
Not good yeast choice for an RIS. it will make it taste like a Belgian beer, not RIS. You’ve also got quite a bit of crystal in there. Personally, I don’t see how you’re gonna hit close to 10% with that grist.
With lots of big pots and burners on hand, consider a small stout with the second runnings.
I agree with the yeast not being the best choice, i’m just the assistant brewer on this one. I’m looking more for suggestions regarding mash and sparge methods to maximize extraction, should we mash half the grains, sparge and then mash the second half with the wort collected from the first? Like I said have not done a big one before and have seen multiple methods regarding the best method.
Should have mentioned this is a 5.5 gal batch.
Obviously you’re aware of all the different methods. All have pros and cons. Personally I’d batch sparge and s
Use the high quality first runnings only for the big beer and the lesser quality runnings for a small beer. Tell your friend not to be scared of scorching the pot. It’s OK to direct heat the mash.
you can but I think you’re over thinking. 10% ABV is not that hard to hit. if you are used to getting around 72% plan for 65%. as others have said mash low and long (148 for 120 minutes would not be out of bounds) add some simple sugar to help it attenuate better.
Agreed on all fronts, Denny. I know this is an equipment/efficiency question, but that recipe will not make a RIS. Even if you did get your normal max efficiency, 18.5lbs of base grain will only yield an OG of 1.088 (I don’t feel like accounting for the lower potential of roasted malts right now) - which isn’t a 10% beer until you get down to around 1.010 FG, all of which is unlikely with the amount of crystal malts in your friend’s recipe.
Not to mention that an FG that low isn’t desirable in a beer like that.
Well, yes. But I didn’t want to ramble. 
OP - we are just trying to help you (and your friend) make the best beer possible. I hope that our posts can aid in that.
Out of curiousity, is 5.4% crystal malt really too much for this?
That’s why I’m here!
Absolutely!