Once, long time ago, I asked on rec.guns how to polish a feed ramp, and why it would be necessary. Well, I'm happy to report that once again, rec.guns pulled through for me.
Polishing a feed ramp, for those that don't know, is done to facilitate the feeding of ammunition. A rough feed ramp has microscopic ridges and such, which cause some types of ammo to get stuck or misfeed when taking a ride up the ramp.
My Argentine HiPower (yes, I talk about this model all too often on this group) didn't feed hollowpoints too well, and it was bugging me. At first, I thought it was due to magazine problems (generic aftermarket mags) but after awhile, I figured a feed ramp polish might be a good thing anyway.
I inquired with a friend gunsmith, who informed me that such a job would cost about $10-20 to be done, and he was willing to help out (but for a fee). Being short on cash, I decided I would try it myself.
I went to Ace Hardware, and looked for something known as "Emory cloth" as per instructions from other readers on rec.guns. I didn't find Emory cloth, but instead i got ahold of some 1500 grit sandpaper -- supposedly used for auto work. This stuff is really "fine" in granular terms. I also bought the 600 grit paper, just in case. The rougher the grit, the more material you are going to remove with each sanding motion. For polishing a feed ramp, you want to remove as little material as possible -- remember, you want to polish, not destry, your feed ramp.
I got home and cut off a small 1" x 1" square, and folded it so that I'd have an edge to rub with. I used a little bit of Break Free, as the guy at Ace Hardware said that if you use oil or water, you can achieve a smoother result.
After only about 10-15 minutes of careful sanding, I started to notice that light refected rather easily off the feed ramp, and I could see a rough image of myself on the ramp. Wow.
I reassembled the HiPower and... voila! It fed a mag of 10 hollowpoints with NO hangups at all... with an aftermarket mag, too.
So, for all of you that have been wondering how to, or if you should polish your feed ramp... I'd say, go for it! Just be conservative and when in doubt, ask questions.