Gimp sprites look terrible scaling down

[Deleted User bye]

Been trying to make a mod with new weapons, textures, and music.

 

One of these weapons is a bacon shotgun, which was took from TmSS.

 

Now, the sprites are very big, so with the help of another forum user's advice, I tried to scale them down without interplation.

 

 

Before Gimp editing: 

 

After gimp editing:

 

 

What am I doing wrong????