So, the new FX "Slow Twist" barrels just a better name for the "Heavy" or is it actually different? A bit generic in the description FX is.
https://www.pyramydair.com/product/fx-stx-superior-slow-twist-liner-700mm-30-cal?a=10147
https://www.pyramydair.com/product/fx-stx-superior-slow-twist-liner-700mm-30-cal?a=10147