So to risk reviving a 13 yo thread, and in a similar vein, what are your experiences with the 25-45 Sharps (6.35×45mm/223)? From looking at pics on the Sharps website, the seating of the 87gr Speer SP appears to be deeper than the bullet ogive in order to fit the AR15 magazine. If true, then the case is really too long for the projectile, right? Yet, I've heard and read so many good things about the 6x45 cartridge but maybe for uses in bolt guns & not an AR? I'm interested in easy 223 AR wildcat conversions (no bolthead change-barrel only) that have deer class capability. So, 6x45, Sharps (these two only need neck expansion),the 277 Wolverine, 300 Hammer (need shoulder setback, trimming, & annealing or purchasing of backordered preformed brass). Any other possibilities? -Mark&Belle