The 260 grain Platinum Tip features a hardened, swaged lead core with the addition of about 2-1/2 percent antimony. This is the hardest lead that Winchester's swaging presses would smoothly handle. The bullet's silver colored "Platinum" jacket is one of the thickest I've seen on a muzzleloading bullet, and it features a very deep hollow point and has an exposed lead base. It was designed and tested to be the "ideal" muzzleloading deer-hunting bullet. Winchester consulted with MMP, and found that the HPH12 sabot, which appears overly long for the bullet, gave the best accuracy from their ensemble of test guns.