.243 Magnum Primers
I use only two brands of Large Rifle Primers: CCI 250 Magnum, CCI 200, and MAGTECH 9 1/2 Magnum. Never had a misfire from either fine product. Both load smoothly and tightly in Lapua, Remington, and Hornady cases, which are all I use. Small rifle primers are different: CCI 400 primers are .020" thick and not meant for .223 Remington applications, while CCI 450 Magnum primers @
.025" work fine in potent .223 loads. All Large Rifle primers appear to be
.027" thick, so primer piercing never occurs in any of my .243 applications.
.222 Remington Magnums and .223 Remington require Small Rifle Magnum primers with hot loads. CCI 400 Small Rifle primers were designed for .22 Hornet, .218 Bee, and .219 Zipper loads is what I've learned the hard way. cliffy