Elk aren't that hard to kill and the 180 gr SST would work just fine as long as you shoot them where they live and if you don't then another brand of bullet won't make a bit of difference. Premier bullets don't make up for poor shooting
That premium bullets don't make up for poor shooting is something I am painfully aware of due to personal experience. (Lost my first big game animal, a cow elk, in 2014 after misjudging the wind.)
That doesn't mean that premium bullets are without benefit. The first big game animal I ever shot was a bull elk at about 110 yards using a 7mm RM and a 162g Hornady BTSP. The bullet hit a rib dead on center, missed or barely nicked the far ribs and came to rest under the hide on the off side. Retained weight was under 48%. Although the spike bull went down, I was not impressed with the bullet performance as I didn't think a single rib was much of a challenge to its integrity.
The next year I switched to 160g Speer Grand Slams and used them exclusively without complaint for 20+ years. The first bullet I recovered was from the end of that period, from a 5x5 bull elk. The bullet had passed through and destroyed both shoulder joints before coming to rest on the far side, still in bone but exposed. Retained weight was over 70%.
My philosophy is to shoot until the animal is down and stays that way. While one shot will usually do it, I have had elk get back up. After doing so I'v never had one come towards me. When that happens and all I have is a bad angle, I want a bullet in my rifle that will expand reliably but in a controlled and limited manner and drive the length of the animal to reach the vitals. Grand Slams have proven to be capable of doing that as have North Fork SS, Trophy Bonded and Barnes MRX and TTSX.
Equally important to me is that none of these bullets (GS, TB, MRX or TTSX) have in any way failed on smaller game or on broadsides. The last few years I and my group have used a lot of AccuBonds, too. While we haven't shot any animals lengthwise, the broadsides we've taken have all resulted in exits.
Another advantage of the premiums (or at least the good ones - there are some 'premiums' I refuse to use based on their design and manufacturers performance claims) is they can provide more consistent performance over a wider range of distances. That is also important to me because, while I practice out to 600 yards, I've had 25-foot shot opportunities where I expected a minimum of 400 yards. I don't want a bullet that will blow itself apart at high impact velocities.
That said, I will be using a 95g SST in my .243 Win for antelope this year. As I mentioned in a previous post, I hope it doesn't perform like the 165g AMAX my son-in-law used on an antelope a few years back.
