Has anyone tried reduced loads in the 300 win mag? How does it affect accuracy? Thanks in advance for your responses.

Not a 300WM, but I run 52 gr of IMR 4895 under a 150gr Ballistic Tip in my .308 Norma Magnum. I get about 2600 fps out of a 22.5" barrel and accuracy is outstanding. Recoil is very mild and cases last forever

35 grains IMR 4198 with 170-grain NP's I had on hand.
Your rifle will tell you what to do / how to adjust.
(Not as accurate as "internet load" I tried. No development needed [75 grains RL-22 with 180-grainers.])

for a 30/30 equivalent....

22 grains of Unique... 150 grain bullet...

58 grains i4320 under a 150 Hornady does 2800 in my Tikka and it is amazingly accurate.....perfect fit for my FF 2 Ballistic Plex scope....ringing small gongs at 300 yds is a piece of cake. In between a 308 and 3006 for snot.

308 Win..........

You can make a 300 into a 308 but never vice versa....here in Wisconsin about 98% of our deer shot under 100 yards....IF I ever hunted the 300 Win Mag it would be that light load.

You can use as low as 60% of the max load of H4895.