The .600 Nitro with 110 Grains of Cordite and a 900 grn. projectile has a muzzle velocity of 1950 F-S and 7,600 ft lb energy. At 100 yds velocity of 1,676 and 5620 ft lbs.
This may seem like a rather dull post to anyone but the ammunition collectors! But if you were actually to go out and try to find to buy these cartridges, you would find it extremely difficult! They are indeed very rare. For me the interest is the sheer scale of the ammunition and the rifles that the first explorers had to carry around for their defence, during the days before the advent of cordite powder.
I think what prompted the post was the fact that in the last James Julia auction, a box of 10 Holland & Holland 4 Bore Nitro Rifle Cartridges estimated to sell at $3-5,000 realised $27,700.00! Naturally I cleared out the cupboard to see if I had any!