Grace's are good, Chapman's are good, and they have a REALLY good instruction sheet, but the most complete set of bits with the best warranty are sold by Brownell. For guns, all of these are good, as long as you use the right bit or driver. This is easiest to do with Brownell.

Many gun nuts use screwdrivers for purposes unrelated to guns. My wife and I once took a trip south in search of a different domicile, with limited space for personal possessions. My complete Brownell set (including British shotguns and such) took up very little space, and came in handy for a number of essential household functions.

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Formerly Model520Fan