the preview should be a sample of the fullview file, if the entire gun won't fit inot the preview image. we try to avoid rescaled previews because they aren't pixel art.
You got the concept of a glock dead on.... but the lineart for this could use some touching up, especially around the grip.
Hrm... the dithering on the front of the gun looks odd and maybe needs to be cleaned up on the edges. Otherwise, great gun!