As the title says I'm going to midblock or halfblock not sure what my plans are considered but some advice would be greatly appreciated. What I plan on doing it doing most of the work with a rotary tool and having a friend clean it up with a milling machine and then get it anno'd so here is what I have in mind for my designs so far and they might get changed even more.

this one is straight forward i'm just going to follow the milling down the side of the gun and leave it open on the top

this one is a little more difficult to where I want to make like a cage design around the bolt.
anyone have any suggestions on how to make this semitrical and any type of cutting but they would suggest for using with a rotary tool other than a cut-off wheel.
Thanks!
p8ntballer