Before you consider polishing the feed ramp...take the Dremel out onto the interstate and let a few semis run over it.
Yes. Fuff is blowin' smoke up your pantlegs. It's what he lives for...
The very first suspect, and the usual culprit in any failure to feed/return to battery problem is the magazine. What kind are you using?
Next in line is the extractor tension. Sometimes excessive tension will allow ball to feed, and choke on decent-quality hollowpoints.
Next is the ammo itself. Are your hollowpoints from a batch of gunshow reloads?
The next thing to check is for a 3-Point Jam. Top off a proper magazine...which you may or may not have at this point...and chamber the top round from slidelock by tripping the slidestop. Do you hear/feel a pronounced "Ka-Chunk" as the slide chambers the round...or is it fairly smooth?
That your magazines may be new...or stylish/expensive...or came highly recommended by the gun shop commando is no guarantee that they're good.
Details are important. A failure to feed means that no part of the cartridge gets into the chamber. If the bullet nose gets in...even just a little...that's a failure to go to/return to battery. The two are often related, but they're not the same.
What point in the magazine does the stoppage most often occur? Is it always the same place...or at random? Top round or last round? Most signifigant...is it always with the same magazine, or magazines?
FWIW...I'm glad that some of you guys stepped up and related the stories of all you old, unaltered USGI pistols that feed SWCs and hollowpoints. It helps me to lay waste to the myth that the 1911 is only reliable with hardball unless extensively reworked/tweaked/tuned/ or prayed over. I have several that date from 1912 to 1945...including some early teens and 20s commercial Colts that can't tell the difference. Hardball...SWC...Hollowpoint...All the same to the guns. They've never been ramped/polished, and they've never had any secret gunsmith JuJu performed on'em...and they do it from the old USGI "Hardball" magazines. I have several witnesses to the fact, and stand ready and willing to demonstrate to anyone who can make the trip.