You certainly can have a volume of a solid as well as a liquid. Liquids have different units; using the metric system, 1ml of a liquid is 1 cubic cm (the size of a cube 1cm x 1cm x 1cm).
It's also a bit pedantic to answer, "It depends on the type and size of feather and how much they are compressed." We know it's going to be a much greater volume, so let's try to find the relative densities and go from there, just for fun.
Lead - density 11342kg/m3; so the volume of 1000kg of lead is
1000 / 11342 = 0.088m³ (0.88 cubic metres = 88l)
The average density of a feather sample (that I found in an online article) is 4kg/m³; the volume of 1000kg of feathers is
1000 / 4 = 250m³ (250 000l).
So a feather is around 1/2841 the density of lead. Or lead is 2841 times the density of a feather sample.
Other feather samples are available.