I am ordering some brass for my .325, and found a good price on once-fired brass/nickel. Is there any difference between the brass and brass/nickel other than looks? Why do some manufactures even add the nickel? I'm loading 200 grain Barnes Triple-X with 67.0 grains of R-19 in a .325 WSM. Thanks, I need to order some more brass and came across 100 brass/nickel, once-fired, for $26 at brassmanbrass.com.