I'm working up some "serious social occasions" loads for my ARs, using 60-gr Nosler Partition bullets. I've always had good luck loading with CCI 400 primers, but am not getting quite the velocities I'm looking for out of my 16" bbls. I'm wondering if using CCI 41 or 450 primers will ignite the powder enough quicker to boost the velocity out of a 16" barrel. Anyone have any experience measuring the difference in velocity between the two types of primers, when other load data is the same? BTW, I've never had problems with pressure signs from the 400s, but am a bit leery of the 41s, as I've read that they may have ignition issues on occasion. Thanks, all!