I have been working/thinking about dust covers for 4 years since I first seen the one by CPTBeaker. I had made my own with Delrin in 2018 but found it too heavy for the spent cartridge to push the door open and eject.
The biggest problem I had was the hinge. I used small nails and could never get it to hinge right. Too much friction.
Here it is 2020 and I was thinking again (look out
), and was looking all over the internet for things that hinge. Well, lo and behold, I came across piano hinges.
Pictured is my 8th try as I tried the hinges all different ways to cover the door. Not the prettiest thing as I need to round the corners. I haven't actually fired it either, but with an empty cartridge and me rapidly pulling on the charging handle it was 50/50 for it to push the door open and eject.
I'm now working on a magnet system which seems to be working manually but the true test will be next weekend.
Now if I mount the hinge like CPTBeaker, then I most likely would not have to use magnets except to hold it closed. I just like the challenge of seeing if I can make it work to only open when fired.