I found my temporary solution to this.
I’ve modified the maxBarWidth variable of the Chart.prototype.renderColumn function in the canvasjs.js.
var maxBarWidth = (this.width * .15);
, I changed it into
var maxBarWidth = (this.width * .063); //or whatever value you like to fit in the chart
Still, its temporary.
Hope the width setting will be available soon.
Thanks in advance!