Where to load a bullet depends on the magazine length, the location of the chamber throat, and the bullet design.
The bullet needs to engage the case neck by 1 to 1.5 diameters, and more doesn't hurt. Magazine length is obvious, the cartridges will need to be single fed if they're too long.
The throat is a whole nuther problem and requires some thought. Loading to a jam means starting over from scratch on the load work up, and the bullet's tolerance for starting from a jam. Loading to a jump depends on the bullet's tolerance for the distance. Most likely the loaded cartridge is too long to load in the magazine when loaded out to a small jump (let's say 0.020), but maybe not in a rifle with a custom chamber.
Look at the tiny volume you'll add to the case interior by moving the bullet 0.01; it's 0.000 75 cubic inches. Compare that to the volume of the case.
However, don't take bullet seating depth lightly with small straight wall cases, the fraction is much larger and alters pressures quickly.