I believe the longer the barrel, the quieter it is because more of the gasses burn inside the barrel before escaping out the muzzle end. How much difference an extra 1.5" barrel makes, I don't know.
A forum community dedicated to Rimfire Central Firearm owners and enthusiasts. Come join the discussion about optics, ammo, gunsmithing, styles, reviews, hunting, accessories, classifieds, and more!