I ordered some D&H USGI mags, very affordable, like the construction, finish and follower, BUT, the feed lips are ridiculously sharp.
How should I go about smoothing out the feed lips? I’ll keep the dremel put away. So what sand paper should I use, what type of file, should I try reshape the lips or just smooth them out?
I’m not just being particular. I have new Colt magazines and the bullets slide out much easier than with these D&H mags.
Shooting and dry firing is all I would do to “smooth out the feed lips” on your magazines.
Do nothing. They are designed to be sharp so you can cut cheese and sausage with them in the field.
The above is the most accurate response you’re going to get. 
The feed lips on those magazines are designed to do a single job, and do it well. If you’re nicking your hands while loading, buy a loader or use gloves. Time working them through the gun will provide enough wear to do any work for you (which won’t be much).
I kind of figured I’d get such responses. I’m not a big AR shooter, I like shooting my pistols much better.
This is a relatively large quantity of magazines, so I don’t plan on running them all until they smooth out.
I’m not wanting to mess up the feed lips. I’m thinking some steel wool or light sand paper or a file may do.
Go to the range and fire 10 rounds out of each magazine for one range session. If you have ten magazines and fire 300 rounds, that would be 30 rounds per magazine. When you are cleaning up your gear, you won’t see or feel any sharp edges.
I WOULD NOT use a file to smooth out the feed lips on a magazine.
Three people have told you simply to shoot with them. Sure, there was some sarcasm, but short of pics with cut up fingers…
OK… Kinda wondering if the AR is a new thing for you. Feed lip geometry is a very big deal, and they really shouldn’t be messed with.
Why buy so many mags then? You’re a pistol guy. (Not that I’m worried about it, your money.)
Why not just leave them be? Sell them off on the EE and grab some PMAGs if you’re worried about sharp edges. I guarantee you that there will be no issues with PMAGs and sharp feed lips. Or load em, keep em, and shoot em. I assure you, the D&H mags are a fine product and they will run like a good watch if you leave them be.
Appreciate the recommendation against using a metal file. I’m not going to the range and burning up 300 rounds of ammo though.
So it looks like some steel wool or sand paper is my ticket.
I got some like this a few years ago. not the top where it could cut your finger, but the inside edge was so sharp it would score deep lines in the case and create failures to load. I considered this a problem and contacted the retailer and they agreed and replaced them.
if I were you, I might try a couple passes with a medium grade of wet/dry paper…
Advice was given and ignored. Do whatever makes you happy.