I wish I had more .22 WMR handgun experience than I do, but the most accurate I've had hands on time with is my Single Six with 9.5" barrel and adjustable sights. With a mild trigger job, an oversize grip to give me more leverage, and the long sight radius, it is a fine shooter with .22 WMR ammo it likes. Plus, the long barrel helps boost the .22 WMR speeds a bit compared to a short barreled handgun.
Unfortunately, I can't see the iron sights like I used to so optics are the order of the day for me. Which negates the sight radius advantage of the long barrel, but not the velocity boost.
Over a chronometer, my Single Six 9.5" has shown 40 grain .22 WMR loads averaging around 1400 fps. With 30 grain loads, the speeds average 1700 fps in that gun.