I have a CZ 527 with a 1:12 twist. I handload and use factory ammo as well. My handload is the 50 gr. Nosler BT and 25 gr. Varget. I've since been using the Hornady Steel case 55 gr. BTHP. Both the hndload and the factory load shoot to nearly the same point of impact and are sub .5 moa loads. I've killed several mouflon/barbado sheep with the Nosler load on our lease in west Texas. All have been shoulder shots and everything has been literally pole axed. I haven't launched the Hornady loads at a critter yet, but when I do it will be a head shot.

The lack of planning on your part does not constitute an emergency on my part!