I have created a stacked bar chart from a SharePoint List View.
My dates show up as 1/1/1900 12:00 AM. I just want the month to show as JAN.
I've gone into Chart Areas > Axes > Primary X > Scale and set the sub Type to Date Time and Formatting to Fixed and set the Label format to MMM and nothing changes.
I've also tried setting the Label Angle and step mode set to a custom one month step to no avail.
Below is how I have it set up:

Hi Greg,
You are probably using a Bar chart with Stacked sub type and the chart uses Categorical X-axis.
You need to switch to XY Scatter Stacked sub type and then pass the date-time field for the Value Groupings X value (under Pivot -> Data Groupings -> Values -> General -> Data tab).

The chart will now be using Numeric Scale - you can change the Sub type to Date Time and configure the date time formatting.

Hopefully this helps.

Best Regards,
Nevron Support Team