How about the guns your usein?

You can run Alliants 4.8 behind a 90gr anything (I currently run this in my Colt 1908 behind an XTP)... They did list 4.6 behind 100gr, IIRC, I was runnin 4.6 behind a 102 Golden Saber.

The .45 is different.

The problem I find with PP in .45 is you can load it HOT, the gun will handle it, but for how long????

I'll only reference you some reading.....

The M1911 Pistols Organization Forums Site - Hornaday 230g TAP .45

The M1911 Pistols Organization Forums Site - Power Pistol and .45ACP

Theres some much better threads in here The loads in the previous threads I know to be good data.