Well, I just got my Hawke SW Tac 30 6.5-20×42 scope and tried the Butler Creek front cover #28. The cover DID NOT fit. It seems one or two sizes too small. My rear cover is still in transit on a "slow boat", so I haven't been able to test its fit.
So, I need to return the front cover and order a larger Butler Creek front cover or go with the Multi-Flex design as suggested by krasiml.
Bob
edit: I called Butler Creek and they don't have the Hawke scopes in their charts, but the representative thought the BC front cover #30 would fit.