It certainly looks like one to me. It is in the Bradshaw Mountains foothills just to the south of StoneRidge in Prescott Valley, where I live.
It pokes it's head up above the other hills around here. Here's a photo to show how close it is to the surrounding development.
If it is (or was) an active volcano I suspect it is long extinct. Just the other direction is Glassford Hill, the landmark of Prescott Valley and a proven extinct volcano.
Photographed from these angles it doesn't really look like a volcano to me. No cone shape. But a little further around the side and you can see where the lava flew 10 to 14 million years ago.
They're not real good photos. The entrance road to the property that I discovered was not closed off or posted but I decided not to get any closer. By cropping my photo you can get a bit better view.
You may notice some towers up at the peak. Those are various radio transmission towers that the town and the county administer. I'd love to get up there to the top at 6,177 feet but I believe it is restricted territory. There's probably a locked gate somewhere up the road aways.
But if that other one, to the south, ever decides to come to life the residents of StoneRidge may be in for a rude awakening.