Ww1 british shell indentification

[zevs]

Hello, I ve got these two shrapnel shells. It seems like 18 pounder/ 84 mm shells. They are both diametr 84mm. But other dimensions are different.
All dimension on the photo

If you have any ideas, please let me know.

Thank you.

 

[Andysarmoury]

they are both 18 pdrs the short one is a Mk XII