For me, IMHO, etc, : I would say it depends on: Practice with THAT gun, sight radius, sights (AS or fixed), weight of the gun (esp. for extended shooting times), and trigger - in no particular order.
* Single action revolver, for me, is more accurate than SA Semi-auto. Forget those long DAO semi's - I can't shoot them any better than a revo in DA. That's the crisp S&W SA trigger IMHO.
* heavier gun = wobbly hand after an hour or two.
* longer sight radius = better accuracy for me.
* lightpost size Adj sights are more accurate for me vs. tiny dots or fixed revo sights. But hey, I'm old and my vision ain't so good...

All that being said; I have a gun with crummy fixed sights, short barrel, etc that I can hit 100% with at 7 yds because I've shot it so much for 15 years. So a couple thousand rounds through the gun probably offsets the inherent issues with the gun itself.

Edit: Hey, that was my 300th post. Do I win a prize?

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But then, what do I know?