We can't find any source for this item (quests reward, drop, etc). It's highly probable this item is not obtainable right now. It seems that the New Shot Across the Bow is obtainable.
My expertise for musket is 618 - this dropped for me after 17 kills today with a GS of 505. I'm wondering if a 600 is even possible because I didn't get anything about 510 GS from this farm. Granted it was only 17 kills but I got 7 no bags, 5 blues, and 4 purples, and all low gear score. This ain't cool AGS.
Dropped for me as a 500 Epic (my watermark is max for Musket) without the last luck perk.
Can anyone confirm the drop of this item?
never gonna drop for you at 600 in a lv 60 zone.