I've tried many bullets in quite a few .30-06 rifles since I began handloading in the mid-'60s. Almost all the bullets have been in the 150 -180 grain range. The bullet I've worked with most recently has been the Barnes 150 TTSX BT. It shoots quite accurately in three old Model 70s, one of which is a Featherweight that has given pretty much mediocre accuracy with a lot of other bullets.
I've never used the bullet on elk, but see no reason why the 150 TTSX BT would perform any differently from other Barnes bullets I've used for that purpose. For a long time, I used a 4350 powder (H4350 for the last fifteen years or so) for 150-180 grain bullet loads in the .30-06. A 4350 is still a good choice, but I tried H4895 with the 150 Barnes and saw an overall accuracy improvement and about the same muzzle velocity I was getting with H4350 loads. However, for bullets heavier than 150s, a 4350 would probably be a better choice.
The 150 TTSX BT has proven accurate for me in other .30 caliber rifles including a couple of .308s, a .300 Winchester Magnum and a .300 H&H.
