The .280 is nothing more really than a necked down 30-06. Recoil with any equivalent loading will be less, but not by a ton. As fat as bullet choice-any load for deer should do for bear, though I would lean towards a bonded type bullet, a sectionalized bullet or an all copper type. Any of which should work well for both.
Big Al's "Take-Em" Style Silhouette Decoys Pro-Staff.