Role
The Loader selects the shell type and powder charges for the next shot. It is the station that turns the firing plan into ammunition, so every elevation value should be checked against what is actually loaded.
How to use it
Pick the shell, add the powder charges from the calculator, and ram the load before aiming. Do not treat the Loader as a background step: if you change shell type or charge count after aiming, return to the Elevator and confirm the new vertical solution.
Operating checklist
Choose the shell for the target, match the powder charges to the range calculation, ram the load, then set bearing and elevation. Loader mistakes usually show up as shots that land at the right direction but the wrong distance.