I bought a new 300 WSM Browning Xbolt for a elk hunt last year and only used it for a walking stick so far. But I used the Federal 180 Grain barnes bullets and never got to see how well they would work on a live target.
I have never had a 300 WSM but I can tell you what I've used for my 300 Weatherby, 300 Win. mag and my 338 win mag. I started reloading shortly after I got my Huskvarna 300 Win. Mag and I used 150 grain bullets, but I was using them strictly for deer. When I got ready to go elk hunting, I switched and loaded 180's. If I was going to use the same rifle for both elk and deer, I'd go with a 165 grain bullet.
For the 300 Weatherby mag. I used strictly 180 grain bullets and used them for both deer and elk. They are a great all-around bullet and I would still use those today if I used that rifle much. If I had a 300 WSM that I was going to use on multiple animals, I'd use the 180's. They work great on elk and sure do kill deer and antelope. If I was going to use the rifle strictly for elk, I'd go to a 220 grain bullet. They still have great trajectory and really do the job with knock down power.
For my 338, which I use almost exclusively now for both deer and elk, I load a 250 grain Nosler partition and it kills dead. I love how it performs in my Browning and what it does to animals. I have killed antelope, deer, bear, elk, moose, gemsbok, zebra, kudu and a few other animals with that same bullet and I have been very pleased. Some may say it's overkill on smaller animals, but I don't find that it destroys any more meat than my 270. I shoot it well and am not afraid of the recoil.
If I were you and I was going out after elk, I would load a 180 or above. I love the knock down power of a heavy bullet.
Ihunt.....I got a new 300 WSM last year and it actually took me a while to get a load put together that was consistent. In the end I was using Win. brass, RL17 powder, Federal Magnum rifle primers, and the Barnes TTSX Triple Shock (boat tail) in 180 gr. With this load I instantly killed my first elk from 250 yds., but shot placement was right on. I used the same load for mule deer and whitetail deer hunting as well. Great results. My brother has the same gun with a longer barrel, and his best load was Win. brass, RL17 powder, Win. magnum rifle primers, and Nosler Accubond 165 gr. This has been a great load for him.
Like most hunters we all are looking for something to keep the deer on our hunting ground and to bring more deer into our hunting ground. Most of the time we just don’t have the room or funding for this to even happen. We lease a lot of smaller properties here in Kansas and we know that the farmers are needing every little bit of ground they can get to make a living. So if they give up any ground at all it’s not much. As I was talking to one farmer he told me he could give up about a half acre...