In most cases, fragmenting handgun bullets are undesirable because their penetration is limited to less-than-adequate levels. This, however, is not universally true as a bullet which can both fragment and penetrate adequately can actually enhance the wounding potential over one which penetrates well but stays together. A prime example of a bullet that can do both are the older 125gr SJHP .357 Magnum loadings. These bullets could fairly routinely shed their jackets in large shards while still allowing the core, which usually comprised 60% or more of the weight, to penetrate 11-13".
Smith, and Wesson, and Me. -H. Callahan
Well waddaya know, one buwwet weft! -E. Fudd
All bad precedents begin as justifiable measures. -J. Caesar