The QLA which incorporates a "false muzzle design" into the actual barrel, a "False Muzzle" and a "Coned Muzzle" are three (3) different and distinct things available. The QLA by TC is made for TC sabots, the cut of the QLA in the barrel does/or can cause deformation of the PRB as it's loaded, so it's not really recommended for that applicatioin. A "False Muzzle" is an actual piece of barrel as an accessory, used by some target shooters to start the patched round ball and impart the groove and rifling to the projectile prior too it's entry to the muzzle of the firearm. Then there is the properly "coned muzzle",, a sweet thing that many don't know about. It's that extra edge of modification that our forefathers had,,that only in modern times have many manufactures tried to replicate for the sole purpose of marketing their products to the unknown for profit.
Don't get me wrong, there is a guy that makes a "coning tool" out there. I've used it with A++ results.