Try working your C.O.L. from 1.100 then 1.110 then 1.120 then 1.125 and 1.130, etc. I believe my 9mm runs from 1.130 and 1.135. The C.O.L should be somewhere between 1.100 and 1.169. The C.O.L could be less than 1.100 but looks like you have already tried that. I've owned two 9mm's s and as I said they both liked different C.O.L's, the Ruger liked 1.135 and the XDM likes 1.130. Now I am not going to get into the the old longer C.O.L and powder charge = pressures changes, at 4.3 grains of Win 231 you will be ok and your rounds will shoot ok. After you find the C.O.L for your gun you can go back and adjust your powder charge later, if you need too. Play around with your C.O.L and and I bet your groups will get better. I can't tell any difference between the Berry's Round, Flat, or hollow point bullets, they all shoot about the same.