Barnes' originalX-Bullets were based on a very simple idea--that if you make a solid-copperbullet, you get rid of all the problems involved in sticking a lead core into ahunk of copper. But all-copper construction created a new problem. Since copperis much lighter than lead, X-Bullets had to be much longer than conventionalslugs in order to make their required weight, and this long length, combinedwith the "sticky" nature of copper as it travels down a steel barrel,led to pressure problems. Years ago, I got hold of some of the very earlyX-Bullets and loaded them in a .270. Out of every five shots, three cases wouldshow normal pressures while two would have their primers mashed absolutelyflat, meaning that pressures were way too high. I know other shooters who haveused the slugs and had no problems at all, but I was not, and am not, a fan ofthe X-Bullet.