The caliber (diameter of the bullet) is the biggest factor in determining the range of useable bullet weights for a given chambering. Next come barrel length and powder capacity. After that it probably does come down to your choice of flat trajectory (velocity) vs terminal energy.
Chamber (case) shape and the ratio of case capacity to bore volume (expansion ratio) is part of the recipe too. But the limits are usually determined by the diameter of the bore. There is an upper and lower limit to the length of a bullet, based on its diameter, for stability. Those "size" limits determine the weight limits. Of course, how much copper vs lead is used in the mfr of the bullet is a factor too.
Imagine a .308 bullet that weighs 500 grains. How long would that sucker be? Off the top of my head, over 2 inches long. You'd either have to extend the throat waaaaay out into what would be the rifling (bore) of a normal SAAMI chambering or you'd have to sacrifice some powder capacity by seating the bullet way back into the case. The latter can really cause severe problems. Even if you managed to overcome these two problems in this example, you'd have to deal with the added bearing surface of the longer bullet. All other things remaining the same, pressure goes up.
Extremely short (i.e., light weight) bullets can present their own problems. Some component mfr made (probably still does) a 110 gr half-jacket "plinker" bullet in .308. The little sucker had quite a jump from the case neck to the point of sealing the bore when cooked off. The result was a notable sacrifice in accuracy. Also, going to faster powders to get the velocity of the light weight bullet up can get dicey in a bottle-neck rifle case.
Published reloads are based on ( I should probably say, "are intended to never exceed") a pressure limit that is established for the SAAMI chamber and bore (land/groove) dimensions.
