i think so. It looks correct, with condition you won't get perfect lay on the wires so it'll usea kittke nore that 12.24 cm2 Have you tried your spreadsheet , the one you used for your transformer ? 0.395 volts per turn equates to how much flux ? 0.395 /100pi = 1.26milliwebers, in cross section of 1/800 m2 = only 1.006 Tesla RMS = 1.42 T peak. See if you can find a recommended operating flux for that core, or stick with 1T rms..