Mine run 15 recoil, 19 main. You can easily tell if you're sprung correctly. Fire a couple mags of your match ammo from one spot. Look for the center of the pattern of ejected cases. Step that off from your shooting position. If closer than 5 feet, you are sprung stronger than needed. (results in harder slide pull than needed, and can get to where you get a failure to eject) If pattern is more than 10 feet away, you are too lightly sprung (can batter the frame and slide). And the recoil and main springs usually "balance with each other" best with the recoil being about 3-4 pounds lighter than the main. The mainspring bore in the grip housing often needs honing to remove the roughness from factory machining.
good luck, GJ