This is a pic of a short tutorial that was posted here on poly a long while back on how to quickly do these. All credit goes to the owner of the tutorial, though, i forgot their name. The white text on the right is just my own notes
I like Nick's thinkin' but instead of slice I would use two rotated symmetry modifiers on half of a cylinder. Which is a bit like the other methods described. So the modifier stack goes something like this: - Edit Poly: Use this to delete the end caps and flat faces on the bottom, as well as flip the polys (or use a normal…