That doesnt stack up
We still sell more .243s than any other cartridge, new and used
what does explain the volume is the Firearms Licencing pushing people to .243 as the bare minimum cartridge for large deer species and it being the "universal" round for foxing, small and large deer.
The 1:10" twist will handle any 80gr Non Lead projectile, we sell a large volume of Hornady CX, Sako Blade, Fox Classic Hunter among others
The pointier and longer they are the more fussy they will be in any rifle not just .243
We have two 100gr options that shoot n a 1:10" standard 1:10" twist
We developed the Peregrine 100gr VRG3 in a Tikka 1:10" 20" barrel