I’ve used a 308 and a 270 on elk - about the same power range as a 7x57. I used heavy for the caliber bullets. After getting too close to a grizzly I carried either a 338 Win Mag or a 350 Rem Mag with 250 grain Partitions for years.
I know little about the big bears compared to many here on 24, but I felt that while in big bear country “use enough gun” was important - to me.
A friend used my first 280 with heavy Speer bullets loaded to 7x57 velocity with great success - as I recall 160 grain Mag Tip Speers was an accurate bullet in that 280 and that’s all I used in it. It was my “loaner” rifle.
