LRF I'ld highly recommend you go to Shilohs web site and in the books order up Orville Loomers book on paper patching. Very basic but well researched and prooven methods.
Evil Twin, if you cleaned those cases your accuracy may jump up a bit. Also have you tried shortening the patch and folding the base? Twisted tails don't do much for accuracy.
As a side note the 27/8 case was the original 45-120 , the 3.25 cased 120 came later and there's good arquements to be made that Sharps may not of ever chambered it.
