There aren't too many Pickel guns around to get much of a basis for comparison and his later pieces are somewhat different than his earlier work. I think that I have seen all of three of his rifles, so what I have to say may be taken with a grain, or two of salt. The 'Crockett' rifle is out of the York School, but has the profile of an Adamstown gun. Look at the work of the Sell's and the Ernst's and you see similarities. Also, the carving on the gun is very different from any other
'York' gun that I have seen. Wish we knew more about it. I cannot think of another rifle that this gun is close to in its decoration, and that is perplexing. It is obviously old and is a mighty fine rifle. Could be that it was made by someone who didn't stay in the craft, or passed away before building too many pieces. Many fine makers switched to masonry, farming, inn keeping, mercantile pursuits and the like, giving up their craft.
Dick