I finally got around to recrowning my Gamo Shadow with that dent in the crown. I think it came out well.
I cut the barrel off at the front sight shoulder using a hacksaw with a 32 tooth blade (the finest tooth I could fine). I went VERY slowly using only the weight of the hacksaw itself to press the blade down. I checked the cut frequently. Then I filed the inevitable junk left from the cut until all was smooth. Next I used a Dremel tool with a cone shaped grinding bit to rough in a new crown. I had trouble with this - it left things pretty rough. So next I tried the Dremel with a round metal cutting bit. This worked much better but a steady hand was required. Those metal cutting bits will chew through the soft Gamo barrel in nothing flat.
Next up was a #8 brass screw chucked up in my drill. I was not able to make progress with this. I tried using Comet sink cleaner and Camo Stainless polish power as my abrasives. After a bit of trying, I gave up on these. I then wrapped the screw in 150 grit sandpaper and chucked it in the drill. The sandpaper was toast after only a second. Hmmm. I was starting to worry.
So I took the screw out of the drill, wrapped it in more 150 grit, and proceeded to grind the crown by hand. I originally thought this manual method would take forever, but it actually worked very well and didn't take all that long. My fingers were a bit tired from grasping the screw though! I did a bit of final polishing using the screw and 400 grit sandpaper.
Attached are pictures of BEFORE (with the dent), AFTER the hacksaw (not in focus, but you can see where I needed to file), and finally the FINISHED CROWN. Those little bumpy looking things in the new crown are lint from the Kleenex I wiped it with. The crown is very smooth.
I do not know what a professional recrowning looks like, but I think I'm satisfied with the amateur job I did. I can't wait to shoot my Shadow and see how it performs. I have this new crown AND a new GRT-III trigger to try out!
Thanks for all the help and suggestions to my other posts asking for advice on this project!
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