with the avaliable bores and action lengths it just might be possible (i dont know) to switch up barrels and receivers to make other carts work...yes some rechambering and creative smithing might be needed but think of the possibilities...

say mixing the 450 marlin barrel with the win mag receiver and having a 458 win mag blr takedown

or switching the 358 win barrel and doing a 358 norma or whelen version.

the possibilities are many i think

they come in the variety of calibers

http://www.browning.com/products/catalog/firearms/detai...t_id=034&type_id=012