Get a raw disk image from qcow2

I want to install Ubuntu (or any distro) as UEFI with QEMU/libvirt and make some changes there at runtime and shut down the machine. This will create a qcow2 disk. If this was not a virtual machine and in the previous step I installed Ubuntu on a real PC instead, I could use a live USB to get access to the hard disk of the PC and do a byte copy of the entire disk. This would leave me with a raw image I could mount on a loopback device or pass it to tools which expect a raw image. Is there are way to access that kind of raw image directly from qcow2 somehow?