Free: Contests & Raffles.
2F for me, too. 3F would work, as the F-number is just the granule size, A grain of powder is a grain of powder, whether it's 8 granules of 2F or 16 granules of 3F.Rule of thumb: 1F=Cannon Powder, 2F=Rifle Powder, 3F=Pistol Powder, 4F=Primer Pan Powder (for Flintlocks).
I see some guys using 3F and some using 2F for a .50 cal. What is your preference if you still use loose powder?