It shouldn't be the case that if you want a .257 hunting bullet in the 100-120 grain range with a good bc, there's only one option at 110 grains that's a mono. Otherwise, you're forced to drop down to 6mm or up to 6.5. You can get a 90 grain hunting bullet in 6mm with a bc of .490, a 100 grain hunting bullet in 6mm with a bc of .515, a 123 grain hunting 6.5mm bullet with a bc of .510 but there's no 100 grain .257 anywhere near .500. Instead, you're looking at a pathetic .393. There's also no 115-120 grain .257 bullet that has a reasonable bc. I could just blame the bullet manufacturers, but it's also the .257 owners at fault (by not creating the demand) who are just satisfied with burying their heads in the sand and thinking that because they mainly shoot short to medium ranges, bc has no significance. Or alternatively, they use an invalid argument that so long as they have reasonable accuracy (at 100 yards) and quite good terminal performance, "who cares about bc".
Your hypothetical 257 bullet wouldn't stabilize in the 1-10 twists of factory 25 caliber rifles, hence the reason said bullet doesn't exist.
