There’s a big difference between being a safe/competent shooter and being a gunsmith.

3d printing a firearm you’re planning to bet your life on is a big ask for someone who isn’t already a gun owner.

Also, if you’re buying a glock slide and parts kit to put in your plastic gat, you aren’t really saving much money.

A glock can be had for nearly $300 on sale sometimes.

I recommend using a kernel virtual machine.

KVM comes with the Linux kernel.

If you want to set it up manually, you’ll have to look into qemu and virtio.

If you want a more virtualbox-like experience, you can use boxes (also called “gnome boxes”), which gives you a very simple UI for setting up VMs (including windows) with networking/shared drives/hardware pass through/etc.

Distrobox is just a set of shell scripts that controlls Podman under the hood. Not only is it like docker, it literally uses the same container format (ContainerD).