You can set the width of the bars using the dataPointWidth property.
We observed that you are using
min-width for setting the height which prevents the the height of the div getting lower than 360px in your case but it is not an absolute value. It would be better if you could follow something like :
<div id="chartContainer" style="height: 360px; width: 100%;"></div>
The label text clips only when the text is very long. If you are still facing some issue, can you please create a jsfiddle reproducing the label clipping?
Also kindly elaborate what do you mean by total graph width.