I have always found that the higher the polish and the faster the speed of carding wheel, the more "blue" or translucent the job looks. I have had good luck with Brownells .0025" wire stainless carding wheels, nothing too fancy. I dont know what all the different factories used 100 years ago, but with what minor differences can actually physically exist between all the possible solutions, I dont think your color spectrum is going to change much from the solution itself. I also really dont like to use anything with mercury or other nasty chemicals either and I dont see the benefit of constantly switching bluing solutions, so I stick with what works and prep the barrels to as close to original as possible and vary the number of coats and carding wheel speeds to achieve different desired results.
