Margins/Padding Left + Right

When I download a packing slip and open in my browser (Chrome) window and hit print there is minimal margins left and right but when I just click print packing slip and it opens in a new tab and the print screen pops up it has double the left + right margins. How can I make it so that the margins are zero on the packing slips that I just print and dont download then open and print?

I am aware of the print setting for margins and have it set to none. When I click print packing slip from an order screen and the new tab opens with print screen up for that packing slip, when I change margin settings it doesnt make a difference. It is like default set to that. Any help is greatly appreciated!!

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