Ross Seyfried wrote in his article Reload Revisited (DGJ Winter 1999) Allaint Blue Dot is the best nitro substitute for the BP in big bores.
Unfortunatly he didn't give the descriptions of the Big Bores, only the follwoing words: ...that use common shotgun description.
At the same time well-known Russian expert Markevith wrote in his book before the war: Big Bore Rifles - from 4G (26,72 mm) till 20G (15,62 mm). Next cathegory following his words: Double Rifle Express (BPE) from 14,66 mm (.577) till 9,14 mm (.360)
(.600 is in Nitro Express cathegory).
As you can see .577 wich is equal to 24G is at the edge between this two cathegories.
I guess nobody tried Blue Dot as substitute in large BPE bores such as .577, but I think it has to work in it, moreover the utilisation of the Blue Dot powder could about right and without visible dirt in bores.
