Another thing that happens is ,if you get some brass with deep primer pockets .When you seat the primer to the same debth as the rest there is a little room between the primer and the bottom of the pocket ,when the firing pin hits the primer the anvil dosn't contact the bottom of the pocket, the primer pellet (the part that egnites) smashes .Resolt no boom. This hapened to me ,I thought it was the CCI primers but after a call to CCI I checked the debth of the primer pockets and found some were 3-4 thou. deeper .Just enough for #####.

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