My .300WM with 200gr NPT has worked but it's 26" bbl isn't my idea of "black timber" friendly! My .300 has had higher magnification scopes as well. For truly functioning in this I like a shorter barrel and quick pointing combined with low power scope or even irons. If you find yourself hunting the edge, or into the shadows you may want to consider a bit more of a compromise in rifles.

I have been using a .338WM with 250gr Woodleigh Weld-cores for years. I cut the barrel to 22" and have used a couple different scopes but always find a low power scope a bigger advantage. I used a .375Win a bit, but felt the .45-70 or .444 would be better. I have used a Remington 600 with a fixed 2.5x in .308W with 180gr NPT-PP a bit but for whatever reason not taken a single elk with it. Point being "dark timber" is a very specific style of hunting, and tailoring your tools to match will help. I'd probably not use the .300 if I had handier choices.

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