Well - too bad that you got a rifle with a caliber you did not want - more expensive ammo for it too, but: if u handload or are willing to buy from rws or norma you have a very nice caliber for moose. This is the calibers the german army (Wehrmacht) used in their m98 mauser. After the World War II there were thousands of them in this caliber left in my country. Many of them are restocked and rebarrelled to 30-06, 6,5x55se or .308 and 9,3x62. Many are also used in more experimental wildcats. But there are still many of them in 8x57. - They are mainly used for moose hunting and are very effective. Norma loads them with a 196 grain traditional and also premium bullet (bonded) (oryx). If the rifle is performing in other respects, I would have kept it in 8x57. In Norway this caliber has a renaissance, and more and more rifles are bought in this caliber, also new ones. You can expect precision in this caliber, also good effect in the deer/moose/bear .
Hope this is useful