I was issued a set of solid Grace Screwdrivers in my initial tool box issue for gunsmithing in the Corps in '73. They are nice but rarely if ever fit the screw slots of most guns. So I don't recommend them.
In the 70's and early 80's, I reshaped a whole bunch of original 19th century small wood handled turnscrews to fit the screws on Civil War era locks and guns I worked on. That's nice for authenticity, but a LOT Of work one no longer needs to do.
I got my first set of Brownell Magna Tip Screwdrivers in the early 80's and have upgraded it a few times to the Master Set, as the upgrades became available along with the super thin bit set. Those thin bits have come in extremely handy when working on original and European locks. I almost never have to custom grind a screwdriver/turnscrew anymore.
Brownell's Magna Tip Starter sets with 22 bits are good, but if one is going to get into gunsmithing, I strongly suggest one bites the bullet and buys the 44 bit Professional Set. Then add the thin bit set as you need to or can afford it.
I have also found the extra bits in the Master set VERY useful for modern guns with allen head screws, but you don't need them for muzzle loading guns.
http://www.brownells.com/gunsmith-...a-tip-sets/magna-tip-super-sets--prod417.aspx
thin bits;
http://www.brownells.com/gunsmith-...it-sets/magna-tip-thin-bit-set-prod44342.aspx
Oh, I have also found it very handy to have at least one extra, regular handle and one slightly shorter law enforcement handle. I have never bought the stubby handle and see no reason to do so.
http://www.brownells.com/gunsmith-...ip-super-set-screwdriver-handles-prod400.aspx
Gus
Edited to add; Oh, a P.S. MOST of the time I have to custom grind a screwdriver today, I can take one of magna tip bits to do it, so I don't have to have a whole screwdriver in an unusual size. Then I just order a replacement bit for the one I used.