I recently acquired a mustang xsp (my first colt) and after leaving my problematic .380 bodyguard I have been reading all I could about the mustang.  After a night of reading and a range day I have a few questions about it.

When loading the mag full only one of the mag FTF the first round because the the bullet nose dives. How can I fix this?

Which leads me to my next question. This only happened with AE ammo but Fiocchi worked fine. But for some reason 2 RO told me colt does NOT recommend the use of fiocchi ammo because its too hot and could wear out the pistol much faster or cause problems. I have never heard of this but I never had a colt before so I dont know.

Anyone know if this is true or just a myth?

I've used Fiocchi ammo for years and never had a problem, mostly 9mm and .45acp. It is full power ammo. I wouldn't call it "hot", its just not loaded "light" like most US production ammo,(AE, UMC, etc....).

I've not had any issues with my XSP using SIG 100gr FMJ, Winchester Train 95gr or Magtech 95gr. The first two have a truncated cone shape and the Magtech is a traditional round nose and I've noticed no difference in feel or how they feed.

As far as Fiocci, I would probably follow Colt's advice. No need to wear the Mustang out, even with it's dual recoil spring set-up.

Never heard that about Fiocchi ammo, and I have shot a bunch through my XSP.  As for the nose dive I would guess it is a magazine problem.  Could be the spring, follower, or feed lips.  Those magazines are made by Metalform, so I bought a few blued ones from Greg Cote as spares.  All four of my mags work fine with all types of ammo though.

The 6 rounder's are the same as factory.
XSP Magazines