Ballistic Effectiveness
Silver bullets differ from lead bullets in several respects. Lead has a 10% higher density than silver so a silver bullet will have a little less mass than a lead bullet of identical dimensions. Pure silver is less malleable than lead and falls between lead and copper in terms of hardness (2.5 Mohs) and shear modulus (30 GPa). As a result, a silver bullet would have no difficulty accepting the rifling of a gun barrel as both lead and copper are common bullet materials.
The terminal impact is somewhat speculative and will depend on a variety of factors including bullet size and shape, flight distance, and target material. At short ranges, the silver bullet will most likely give better penetration due to its higher shear modulus, and will not deform as much as a lead bullet. A 2007 episode of "Mythbusters" demonstrated a greater penetration depth of lead bullets vs. silver bullets. Results cannot be considered conclusive, however, as the show utilized a 250-grain lead slug in a .45-caliber Colt long shell vs a lighter (190-grain) silver slug fired at closer range. And later in a 2012 episode, it shows that silver bullets suffer in poor accuracy compare to lead when fired from the M1 Garand. Michael Briggs also did some experiments with silver bullets compared to lead bullets. After making a custom mold to ensure that the sizes of the silver bullets were comparable to the lead bullets, he fired them. He found that the silver bullets were slightly slower than the lead bullets and less accurate.
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