无法使用json将大量数据推送到控制器

I have a webgrid with lots of rows and each row has a checkbox. If I select 10 rows I am able to push the data to my method in the controller and update the database. Once the rows selected are more than 20, Nothing happens. I cant step into my method. Is there a limitation I can pass with json? What do you think is wrong?I have a webgrid with lots of rows and each row