PHAK is not clear about VFR flying into Warning Areas. Warning areas are similar in nature to restricted areas
, which says IFR can be cleared through the airspace but VFR is not mentionned.
Sectional uses the same visual cue as Prohibited and Restricted but that's a little thin to draw conclusions.
AIM says Prohibited and Restricted are ruled by 14 CFR Part 73
but nothing seems to rule Warning Areas: Warning areas, military operations areas (MOAs), alert areas, and controlled firing areas (CFAs) are nonregulatory special use airspace.
Do you need clearance to fly VFR into a Warning Area?