Colt Combat Cmndr - Federal or Speer Lawman FMJ ball ammo
I'm no expert, but Clint Smith is. Clint's quote:
"...Because the 1911 is basically a defensive handgun, I’m not concerned about tight groups. I don’t bother with expanding hollowpoints that could cause feeding problems. For absolute reliability, I shoot only high-quality ball ammunition. That big .45 slug doesn’t have to expand to be effective.”
From Guns and Ammo, September, 2001.