Hey Andrew, I'm running 2.9gr of AP50 through mine at present wit the 100SWC's, soft but groups OK at 50yds. Anything under that and it's a one hole group. Over the chrono it's just running a little over 1000fps (as you are), I haven't done a lot of work with the 9mm as it's purely for fun for me.
I'm running .357 spartans, exactly the same as my revolver. It's not true that I am lazy, just frugal
I couldn't get AP70 to shoot and as you found also that there was too much unburnt powder. When I ran out of my tin of 473AA I ran AP30 for a while with 3.2gr but as I had 6 tins of the 50 decided to give it a go. It fills the case up to the base of the projy and meters fine through the Dillon so it's a bonus, plus it's around the same burn rate as the 473AA.
I have found with my service loads that AP/AS30 will give fantastic consistent results in a 3.0 to 4.0gr load but due to it's coarseness will not throw consistant small charges. I do know someone who uses it in their 32S&W, and was until recently in the NSW team, but he doesn't throw them, each one is measured.