At 100 yards on Iron sights it is fine for its use.
The 1:9 is ideal for a 55 gr bullet. The typical .22LR is about a 40 gr bullet. That doesn't require as fast a twist, but 1:12 is probably optimal. 1:16 sounds too low for good stabilization. I tracked down a web page with common twist rates for T/C Encore/Contender barrels. The cite 1:16 for rimfire .22. Faster rates for center fire. See twist rates.
Not that familiar w/ the Cienor AR-15 conversion but since you reference the AR barrel I'm assuming it uses some sort of chamber insert to provide a .22 LR chamber. That being said there will be a lot of smooth bore to travel before the .22 pill gets to the forcing cone in the actual chamber and engages the rifling of the AR barrel. My guess would be that that smooth bore portion in the chamber adapter is somewhat oversize compared to the groove diameter of a .22 LR barrel. This would permit some gas blowby and possibly allow the bullet to tip slightly and not engage the rifling in a repeatable manor.
If you are happy with what you have and having fun with a "plinker", god speed. However, if you want to bring up the accuracy and fix the barrel twist at the same time look around for a conversion kit that swaps out the upper receiver/barrel for one fitted with .22 LR barrel/bolt. It costs a bit more* but you gets what you pays for.
Don't forget to clean thoroughly after an afternoon plinking as .22 LR leaves a lot of unburned power behind and lead bullets will fowl up your good AR barrel.
Regards,
GtG
* A bit more being about what a "high end" .22 rifle would cost, but you get to practice more w/ your "badass" black rifle!