Date Format Issue

I am creating an application to show on-call schedule for teams within our company. As a part of this, we are implementing an "on-watch" feature - which will allow another person to handle on-call duties for a specified time period.

On the on-watch screen, I can enter the start and end times for on watch for a specific date (ex. 2:00pm-4:00pm) as military time, and the times convert properly which you click the "add" button on the screen (1400 converts to 2:00pm).

However, when I hit the "Save" button to store the change, the grid used to the display the update shows the time being off from the time entered. I could be anywhere from several minutes off to a couple of hours. I've created log files to see what's in my fields, but nothing looks out of order there. (I have an attachment with log file included also).