Interesting that you should consider any centerfire as 'small bore' when for generations that label has been understood to apply exclusively to .22 rimfires.
Using the accepted definition, my pick is my factory customized third-generation K-22 Masterpiece (Model 17) six-shot, six-inch barrel (pinned), recessed chambers, wide rib and trigger-stop adjustment. It has TT, TH and TS. As it came from the factory it was a mess, and I returned it on the same day I bought it, with a three page list of its deficiencies, after only 50 rounds fired. Six months later, it was returned to me, perfectly blueprinted. This is the most accurate revolver of any caliber or make that I've ever fired, and on any given day can outshoot most target automatics and iron-sighted .22 rifles. It's one I'll never sell.