According to my book (Sixth Edition) all of the Hornady 150-155 grain bullets list as 69.5 to 79.1 with Reloader-22. All of the Hornady 165-168 grain bullets list as 66.9 to 79.1 with Reloader 22. That includes the Interbond, SST, A-Max and etc.
I do not load for the 300 WM but I am sure there are at least 1 or 2 around here that do. I am sure they will chime in to offer some advice. I know when I am working up a new load sometimes a shorter COL will give me a better grouping then one seated just short of the lands. I have a .338 RUM that I loaded with Interbonds and Swift Scirocco's and was not at all happy with the results no matter what load or length. Sure it was good enough to hit the kill zone, but is that actually good enough for a reloader? lol

I loaded up some Hornady Soft Point Interlocks and they shoot great. No high tootin fancy smancy plastic tip or anything, and I love that bullet in my gun. So goes the story of reloading.