After testing this morning, a full turn of my Lee FCD eliminates all bullet creep in my S&W +P rated Airweights using 38 Spl +P 158 gr LHP loadings (5.6 grs Power Pistol and 5.2 grs Unique, IAW Speer manual).

My protocol for adjusting my Lee FCD is to, with ram up, bring down FCD die until it touches shell holder. Bring down ram. Turn out the FCD adjuster all the way or nearly all the way. Placed sized 38 Spl casing in shell holder and bring ram up and run case into FCD (no crimping or sizing will be done since the adjuster is out and doesn’t engage shell casing mouth). Then turn down the adjuster until it stops when it just touches the shell case mouth (don’t force the adjuster down, just make contact with shell case mouth). Bring ram down, remove case and then make one complete turn of the adjuster downward (I usually make a reference point on top of the adjuster with a black sharpie to determine alignment)...then start running loaded cases through die.