First make sure the loading block is sealed with a good wood sealant, like shellac, so that the wood does not absorb your Moosesnot. Then soak the patches before putting them and the ball in the block. don't leave this for a long time storage, as the patches deteriorate in the air, and the lube does tend to dry out a bit. Load your block before going out the day you are hunting. If you hunt a weekend, or a couple of days in a row, I would not worry about the PRB in the block. But If its going to be a couple of weeks before I get back out in the field, I would take the PRB out of the block, throw away the lubed patches, keep the lead balls, and use them again with new patches, just to be sure of the quality of the patching.
Try using something simple like olive oil and beeswax in a 4:1 mixture. The wax is the thickener, and it will hold the oil in the cloth. If you have castor oil, or ballistoil, or some of the other oils recommended ( NAPA makes and sells a water soluable oil) use that instead of going to the store to buy a bottle of olive oil. Check the member resources on the index page for Stumpy's Moose milk and Moose snot, for mixing forumlaes. We are fortunate to have the man who spent so much time fiddling with this stuff as a moderator of this forum, so it would seem wise to use his talent to our best use, and not go wandering off thinking we can invent a better wheel! The actual mix often varies depending on what part of the country you live and hunt in, and how cold or hot it is. You need more wax, for instance, when its warmer out, and much less when its below freezing.