I have been out of reloading for a while but back in a big way.
I need deer load for 300 wm,165 to 180 grain. I have RL19 and IMR 4350.
Also what primers, componants are hard to get, I need more than one option.
I tend to shoot a little heavier bullet to maximize range. H1000, fed 210m or 215m. Win or nosler brass. 208 amax.. Berger 210, 215. All extremely accurate and proven terminally. I'm sure you could sub statute a 180 grain bullet but those listed components work the best in my 300wm. H1000 is very temp stable.
I use rl22 in my 300 win with 165 hornady bullets, but rl19 would do you well too. I often hunt in dang cold temps. so I use fed mag. primers from the get-go so the load's already worked up with them.
If you keep your bullet weight to 150-165gr I4350 would work well enough. Around 74 gr.(work up to it) of I4350 with a 150gr in a 300 win will do 3300 fps in most rifles.