How do I smooth the edge of this CSG?

[Headstackk (Stacky)]

I’m trying to smooth the edge of this shotgun that I’m building:

I made a Union part and put it on the edge of the part that I’m trying to smooth:

The result is pretty satisfying, but how do I deal with this particular part?

Here’s a messy way that I used to create this Union:

I know I could have use plugins and there’s definitely a better way to create such part, but in this current scenario, how do I resolve this? My ultimate goal is to smooth the edge of this Union.

Thanks!

[rawsputin]

Make a scaled up negative part of the edges I’ve highlighted. You can do so by duplicating them, separating the unions, make the initial parts bigger but move away the negative parts towards the outside, keeping them at the same angle. Also extend the initial part towards the brick that’s sticking out. Then use that scaled version as a negate part to union with the brick that’s sticking out. This will carve off the sides that are sticking out while keeping the brick molded with the handle.