I have two greaseguns.
A smaller trigger type and a pneumatic one.
I tend to use the pneumatic as it allows one handed use easier. Other hand holds a prybar to raise the bronze plate to allow grease to get under it to ease steering effort. (A tip from Phil at Allon White)
The non cartridge filling is what I do from the tin with the plastic disc.


Plus Four MY23 Furka Rouge