It is Kammer J B 7Hi Steve,
I think I've said it before, but I don't understand how an MG Tschako could have a Jäger Btl 7 Feldzeichen.
The machine guns were either in a separate unit, with their own uniform and the Tschakos that you show, or would be part of an infantry / Jäger unit and then wear the uniform and headgear of that unit.
Regards,
Lars
P S I have no doubtsIt is Kammer J B 7
Steve