I changed the following CSS in pos.css which was related to printing of pos receipt:

.pos .pos-sale-ticket{ margin: 0; margin-left: auto !important; margin-right: auto !important;

border: none !important;

font-size: 13px !important;

/* width: 266px !important; */

Converted above line in a comment so now the size can be changed to whatever you set in the css below:

.pos .pos-sale-ticket {

text-align: right; width: 700px; /* <--------- Old was300px  and new is 700px*/

background-color: white; margin: 10px;

padding: 15px; font-size: 12px;

padding-bottom:30px; display: inline-block;

font-family: "Inconsolata";

border: solid 1px rgb(220,220,220);

clear: both; overflow: hidden;

}