Wife has been shooting Berger 130gr otm with her 6.5 creedmoor elk deer and antelope and it performed very well. So far this year she dumped a good mule deer buck at 456 yards with a Sierra Tipped Match king and I was impressed with that bullet....
OP mentioned barnes ttsx. You certinly dont need to for performance, but if you dongo with a mono In a 6.5cm the LRX probably would be a better choice, it’ll hold velocity longer and expand at lower velocity. Factory loads in my 6.5cm 24” barrel at 1800’ DA doesnt go below 2000fps until 460 yards…so more than plenty of velocity inside 300+.