I use the 210 grain TTSX in my 338 RUM. It has a higher BC than the 185 grainer and thus bucks the wind a tad better. This combination took down a nice 6X6 bull 2 years ago. The bull was 358 yards at a 21 degree down angle. He was double lunged with a broadside shot and went about 20 yards and pilled up. Having said all that either bullet will totally hammer an elk.
I have killed 6 bulls altogether with the ttsx with 180 grainers out of a 300 win mag, couldn't ask for a better bullet, every bull I killed with them if it didn't drop it in its tracks it didn't go more than 50 yards