I was dropping off a CM9 (only 100 rounds fired) at my local gunsmith to have my slide treated with Cerakote. While we were talking he looked at my feed ramp and asked me if I was shooting hollowpoints exclusively. I remember looking at the feed ramp when I first got it and there wasn't anything remarkable about it. After 100 rounds of round nose frangible and maybe a few JHP there were some deep pitting marks on the feed ramp. I had him polish the feed ramp and it looks better, but I've never seen pitting before on my other handguns. Is this normal?