I just recently bought a 44 Mag Handi-Rifle from my local Gander Mountain store, and the serial number begins with HX. The FAQ's index indicates it is a 2007 manufacture weapon. My wuestion is this....does the HX prefix denote that this weapon has the 1:20 twist barrel made by marlin or the old slow 1:38 twist? I can't find the old thread about the change in barrels. Please advise......