Its been said the Sigma 100-400 is not a quick lens for AF,one of the most difficult shots to get in BIF is the bird flying towards you, i think it did well here, if you look at the ISOs you can see it was not a good day for testing.
None should be missing, its the complete burst of shots, remember this is just an AF test no editing has been done.
None should be missing, its the complete burst of shots, remember this is just an AF test no editing has been done.