to reduce recoil, a lighter bullet or less powder?

For instance, say you want to reduce the recoil of a 300 WSM. The data for a lighter bullet shows more powder. A 180 gr using IMR4350 has max of 65.0 grs and a 130 gr has a max of 72.0 grs.

So what would produce less recoil, lighter bullets or less powder?

I'm thinking powder is the correct answer but I've been breathing Hoppes all afternoon so I may be a bit fuzzy.

Both?

small powder IME. I've shot 500 gr 470 NE cast with 50ish grains of AA5744. similar to a 375 H&H. same for 400 gr 416 out of a rigby.

Lighter bullets produce lighter recoil....
There is a noticeable difference in recoil when I shoot my 300WinMag using 168's,180's and 200gr. bullets....

All things been equal, powder charge has the greatest effect in the recoil formula. For example many years ago i bought my wife a 280 Rem mountain rifle, just the ticket to launch a 140gr bullet at near 3000fps. To much recoil and muzzle blast for her! So we went with a 175gr bullet and 51.5gr of IMR4350 for about 2650fps, nice rifle to shoot now, and will down any moose that walks.

The .300WM with 72grs of powder kicks alot more than a .308 with 42grs. Drop 30grs of bullet weight and it has much less effect than 30grs of powder.

Furprick provided a great example. My Ruger #1RSI in 7x57 loves a max load with a 145gr bullet, but that little 20" barrel sure jumps when I touch off a round. I tried some 160 grainers with less powder and things seemed better. I only shot a few, but I have more loaded up and will really put that theory to the test.