Fake it 'till you make it

Fake it 'till you make it, words to live by.  I did some more work on my not-actually-an-M16A1 project.  With my lower machined, it was time to do something about the bare aluminum.  Since this is a "low budget" project, I didn't want to have it anodized.  Budget aside, matching the color of the original upper would be nearly impossible.  Even the real things often didn't match.  For what I'm doing, I also don't need the long term durability of anodizing.

Googling around, people reported that Rust-Oleum Dark Grey primer is a close match to the original Colt XM Grey, so that's what I decided to use.  So, how close is it?  Pretty darn close.  Here's my freshly painted lower next to the least worn area of my original A1 upper for a color comparison:

It actually turned out great and the Rust-Oleum color is a very good match.  I cheated a little bit because of what I had planned though.  I mixed the primer with clear KG Gunkote, giving me what amounted to a tinted clear with the durability of Gunkote.  If you just want the color, this step isn't necessary because the primer will do fine on it's own, but I have more planned for it.  While the color was perfect, there was one glaring problem with it, which you can see here:

The lower looks brand new, because it is.  The color is right, but the fresh painted lower does not match the heavily worn finish of the original upper.  This is where the "fake it" part comes in.  I'm going to artificially weather the finish to try to match the original.  This is why I mixed the grey primer with clear KG Gunkote, it gives me more film thickness without the color being too dense.  The way the original anodizing is done, it looks semi-transparent when it's worn thin and the primer alone won't do that(I mean, primer is made to actually cover surfaces after all and it does that great).

The idea here is to wear through the paint in the areas where it would have been rubbed a lot.  Ultrafine sandpaper is too harsh and not flexible enough, and even scotch-brite is a little bit too abrasive.  I settled on a Mr. Clean Magic Eraser.  Magic Erasers are about the same as 5,000 grit sandpaper.  It cuts through the paint very slowly so I could thin it down without going too far.  It's not a perfect match and it still lacks the scratches from use that the upper has, but for my first project using this technique I think it turned out alright.