I don't know about the answer to your first question for sure. As for whether or not the ballard barrels are better than microgroove, this has been a point of discussion for years. In my own experience, I've come to the conclusion that this whole issue is largely fable if you cast and load carefully. I started casting bullets for 30-30's, 35 Remingtons, and a Marlin 45-70 in the early 1970's, completely unaware that there was supposed to be a big problem with microgroove barrels. I guess I didn't read enough gun magazine drivel back then. I just read up how to cast in an old Lyman manual and went at it. My 45-70, 30-30, and the 35 Remingtons that I loaded for were all microgroove, and all proved to be very accurate with both jacketed bullets and cast ones. Decades later, I started reading these discussions about how bad microgroove barrels were supposed to be with cast bullets. I must have screwed up all these years, loading my wheelweight-plus-a little pure lead projectiles with loading-manual data and using them for shooting and hunting. My biggest screwup was probably slugging my bores and using properly sized projectiles for each rifle that I loaded for.