I just bought a polished stainless 75b and rounded the trigger guard on the very next day I brought it home. Yes my heart was pounding hard.
The whole process took about 3 hours. I was anticipating either ruining my pistol or getting frustrated or scared in the middle of the process and trying to find a machinist or gunsmith to finish it for me if he didn't laugh me out of his shop first. The 3rd option I was prepared for was to be stuck in a quagmire for months sanding the guard down by hand as I got closer to the final shape. So to have the pistol completely reassembled within 3 hours after starting was nothing short of Divine intervention in my eyes.
The steps I took were:
1. Field strip and remove grips
2. Gorilla tape entire pistol. No tape applied to trigger guard area where it will be ground on
3. Bench grinder. Keep firm grip on pistol. Let the grinder do the work don't push too hard and keep the pistol moving. The guard seems to be crowned in the middle so leave extra material there. The idea is to remove most of the material here, get it in rough shape and do the final shaping with a Dremel.
4. Put in rubber padded vise. Don't overtighten and crack the casting.
5. Dremel with drum sanding bit. I think I went through 3 pieces of sanders. I used speed level one and kept it moving around constantly, never stopping in one place. It was very controllable. I always used 2 hands on the Dremel. Do your final shaping with this step. I removed the pistol a few times from the vise to check the shape in the sunlight. I changed the way the pistol faced in the vise towards the end of the sanding process so I would get the same approach angle from holding the dremel with my dominant right hand. Get your final shape here. The rest of the steps are to remove any grinding sanding marks.
6. Emory cloth. I went to Ace Hardware and bought one sheet of medium and fine grit Emory. I cut strips about 1/2" wide. I went through about 6 strips each. Starting with the medium strips first. I used the strips like I was shining shoes. The medium grit smoothed things out really nice. There was one area where I had a deeper gouge from the last serration on the trigger guard so I went back to the Dremel again in that area. Keep it moving lightly with the Dremel even though the gouge is in one area. The idea is to feather it in the area. Use the medium Emory again then follow up with fine grit over the whole area. The Emory wears out quick so use a new area on the Emory strip until the strip is worn out then get a new strip. At this point I removed all tape from the trigger guard and feathered into the factory polished area.
7. Bench grinder with buffing wheels. Have a firm grip on pistol! I used fast cutting Emory first followed by stainless rouge. Again keep the pistol moving let the buffer do the work, don't push too hard. I stopped here. I could have used white rouge but the trigger guard was already becoming more polished than the factory polish.
8. I had one hard to get area where the guard meets the frame at the front. Here I used the Dremel again with a felt buffer bit and Dremel 421 polish.
9. Remove all tape. Hardly any glue residue remained on pistol. Any small spots of glue rubbed right off with my fingers. I then wiped down entire pistol with the inside of my old cotton sweatshirt I was wearing.
It turned out way better than I hoped for. It looks like it originally came from the factory like this.
