Kirin is weak to dragon and dragon alone. Use sword and shield against , its a really effective way to clear through its tough hide. Any other weapon like G-sword , lance , ect. will bounce off. Hammers work but its really hard cuz they re meant for really skilled hunters that know how to evade monsters without getting spanked around all the time. With the hammer a good offence is a good defence as they would put it.
So pretty much go with s&s , it will serve a good cause. Use high raw attack power against it thats over 230 or 250 with alot of affinity. Over at least 20 %. Hope this helps
I Thought Kirin was weak to fire attribute as well. Not as much as dragon, but still weak to it.