I have a 4" 686+ and a 6" 686 (six shooter). I would not want a shorter barrel than 4" for range or HD use because the shorter the sight radius, the less accuracy. Personally I like anything between 4" and 6" fine; I do not find the 6" all that heavy, and the weight helps manage recoil. 38 spls. feel like .22LR rounds with the 6".

Unless you are carrying the weapon concealed, I think that the OP will do well with a 4, 5, or 6 inch 686.

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Army veteran, NRA Life Member