Yeah they look a little out of focus and perhaps need a little longer shutter speed.
I don't know your lens very well but on my tiny iPod viewing screen, these images look slightly out of focus and dark.
Exposure bracketing is a good suggestion. Make sure your camera's metering is in Center Weighted or Spot. Even with a 300mm you should be able to get a sharper image than this.
And like someone else said, keep trying and changing shutter speeds. Nothing is lost but inexperience. Many have taken not so good pictures of the moon and look at ours now.
Edit:
Just to further illustrate our suggestions and help inspire you.
Here a a few from what might now be an average quality dslr and an average quality lens. These were taken just about an hour ago with my K10 and SMC F 100-300mm. The first is an uncropped, unedited image at 1/350, f11, iso 400

This one is a crop of a similar image still with no other edits and at the same settings

These were with the camera mounted to a tripod and using a remote to trigger the shutter though really at those speeds using your finger would most likely make little difference unless your tripod is made from Fuzzoodles.
Keep having fun with it.
(Exif reports Spot Metering, the lens type as "smc PENTAX-F 100-300mm F4.5-5.6 or Sigma Lens" and the temperature was 12 C)