Miller, I think they used what was on hand when a rush order came in and the proper, lower grade, barrel set was not at hand. If they had 10 G grade barrels on hand but no H grade they just used what they had. Or it could have been at the request of the buyer. H grade with G grade barrels for an extra dollar or two. I think Lefever was really a customer driven company a lot of the time. If a customer asked for it and paid for it then they made it. That would explain some of the mismatched things we see with Lefever.
I have also seen a twist and Damascus barrel combination and a steel and Damascus set. Then you come across the DS guns with Damascus barrels. Seen one of those two. Wish I had bought that one. Lefever are great because they are so varied in what you find. Of the thousands of Sterlingworths you see there are maybe five to six combinations, of the Lefever guns you will find many times that.
