With 124 it won't be to bad, but with 115 You will be tipping the rim..
That's the only issue with vv 3n38, otherwise it's probably one of the best powders for 9 major.
I have never used Lee crimp die, dillion and redding for me.. They both have Work great.. And have never had to trim brass...not very common with pistol brass..
Load fmj and coated bullets.
This is the one I'm currently running, works great does not get in the way of my grip. The others do.
dawsonprecision.com/mag-release-button-1911-2011-hicap-lo-pro-by-dawson-precision/
start by putting back in your stock barrel and running your BBI loads. KKM barrels have tight tolerances and can be rather finicky with Ammo. The stock barrel will give you plenty of accuracy.