Having a hammer snag on a draw in a self defense scenario could ruin your whole day.
I only have two revolvers, a Smith and Wesson 638 Bodyguard snub nosed revolver that has a shrouded hammer and can be shot either double action or single action and is snag free.
My other revolver is a Ruger SP101 snub nose in 38/357 Magnum and I did bob the hammer on that one, did not affect reliability one bit and I can still shoot it single action if I want to, at the range with the handgun safely pointed downrange at the target, I pull the trigger back just enough to bring the hammer back where I can get my finger on my weak hand between the hammer and the frame and then pull the hammer back until it is fully cocked.
I shoot double action mostly, in a defensive situation you will probably only run double action, however it is nice to have and practice single action.
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