Don't polish the ramp unless you really know what you are doing. That little bump or gap between the ramp and barrel is necessary for proper feeding. Once the ramp is polished back too far on the 1911 the frame is shot, I've heard of gunsmiths that can repair the damage but is sounded like it would be more expensive than buying a new gun. Go to a gunsmith with .45 experience, the feeding problem could be something as simple as an extractor adjustment or feed lip problem with the magazine.