I am a newbie to loading pistol rounds but I did manage to do a plunk and spin test on the round at an OAL of 1.100\”.
It is definitely clear of the rifling and spins easily.
I think the round did not have enough umph. (charge) is what caused the problem.
A problem I still don\’t understand fully why the slide would not pull back ( I hit it into battery) until I discharged the round.

I didn\’t want to use 6g with a plated bullet, but went ahead and added 0.5g to bring the charge up to 6g of Silouette.

So far that seems to have solved the problem and I am getting the 1050-1150 FPS that Berry;s recommends for their 124g hybrid HP.
Not too sure about accuracy yet.

FWIW I am a little east of Springfield Billy. Out in the country.