The Demolition Ranch team responded to viewer’s requests to see if its possible to cut through a utility pole with (enough) rifle fire. Short answer: yes.
Sure, you can probably drill through anything if given enough time and ammo, so the DR crew grabbed a gas-piston POF 7.62x39mm caliber AR platform and went to work with a stack of steel cased ammo.
Of course it took two days to pull it off, but there is a kitten story in there somewhere to account for that.
Source Article from http://www.guns.com/2015/11/02/can-you-chop-a-phone-pole-in-half-with-a-rifle-video/