I was wondering as I just started reloading my .40 with Speer brass and Winchester Primers. Every fired round shows some discolouration around the edges of the primers. Not pure black carbon from a true blow by, but more akin to a dusting/dirtying of the primer pockets. Would this cause my velocity fluctuations that I have been getting? (+-100 FPS Spreads) from some minimal blow-by? If so, I'm gonna be unhappy as I have 2900 WSP primers left... Oh well. time to start on .38 Spec I guess...... I'll post some pictures of the rings-around the primers once I get some time... I'm thinking that the primer pockets of Speer brass may be sized to CCI Primers?