Barrage: 6 hits crits is slower than 6 normal hits?

well... i do not admit that i trained this viper up using my main account.

and i am now humbly asking for information which i am hoping i am able to find.

I tried to find the success % of the stance effect in many places already, but to no avail. should you have the information, please guide me.

Thank you~ ^_^

It should say in your skill book it's 50% I think.