Your M-1066 is a solid, heavy pistol. I find the W-W Silvertips in 10mm Auto to be powerful yet controllable using a good Weaver (recoil management is one of the Weaver's advantages) and if I carried a 10 mm for protection, from 2 legged predators or 4, that is what i would load it with.

DMattB is right about the lighter, less potent "FBI 10" loads, which propel the same bullets at the same velocities as the .40 S&W. A .40 pistol would be more compact, probably lighter and hold more rounds than your 10mm Smith.

Many state and local cops fondly refer to agents of the FBI by using the agency's initials as an anacronym, calling them "the FeeBees." The FBI 10mm loads are often thus called, "the Feeb 10," "the 10mm Lite" and, my favorite, "the 10mm Minus-P."

The 10mm Auto is a great cartridge and your M-1066 is a fine handgun to shoot it from.