Generating bitwise identical keyrings with GnuPG 1 + 2

[Ángel]

On 2019-08-18 at 08:24 +0200, Mihai Moldovan wrote:
> So, to summarize, if I process a keyring file generated by gpg 2.2
> with a 1.4 binary, i.e., read-in the former, export all keys and
> import it again, gpg 1.4 generates exactly the same file as it would
> when importing the keys directly.

I'm baffled by this.

Could you run gpg2 --list-packets on both keyrings and compare their
outputs?

That should hint which packets are being included by 1.4 that are not by
2.2

Best regards