Ouch. Um, hate to be the bearer of bad news, but the old ziploc + rolling pin trick really only works for small amounts of specialty grains and steeping-extract batches, where you're not expecting to get much fermentable sugar from the grain. With a partial mash, you're actually trying to get a portion of your sugar from the grains, and without a grain mill of somoe kind, your efficiency is going to probably suck---or you'll have a stuck sparge. Either way...next time, I'd get my grains precrushed from the HBS.
I'm crushing about 4# of Munich Malt to go along with 5# of German Pils LME. Do you think that's too much to crush? I've got some extra LME (4# extra, to be exact) I could use and just go with steeping the malt.
Well, if you have a local homebrew supply shop, I'd take it there and get them to crush it for you. If you don't, then what I'd do is this:
Double-up with large ziploc bags, put the grains into the inner bag (as much as will fit while still allowing the roller to press the grains against the bottom surface), press all the air out and seal both bags tight.
Crush them thoroughly with the roller.
Repeat until all 4# are crushed.
Mash the grains, sparge, etc.
Add the 5# of pils extract to the boil around 20 mins before flameout.
About 10 mins before flameout, take enough of a sample to get a hydrometer reading. Cool it (quickly!) to 60f, and take a reading.
If your gravity is roughly around what you were expecting (I'd assume low efficiency), then you're fine. If it's low, then add enough extra LME to hit your gravity prior to flameout, making sure to stir thoroughly.
yeah i'm another victim of the rolling pin method. don't risk your life or anything, but getting your grains milled helps a lot.
also, so that in the future you get the most targeted responses, a thread title like "crush grains without a mill" or something like that will probably get you the most people who have experience with your problem.
i REALLY don't mean that in a bad or critical way, just that the threads with descriptive titles seem to be the ones with the most input. cheers!