Custom EditorGUI Problem

this is my custom editor Script:

 target.ammoLeft = EditorGUI.FloatField(Rect(0,80,250,15),"Ammo Left in Current Clip",target.ammoLeft);
     target.maxAmmo = EditorGUI.FloatField(Rect(0,100,250,15),"Max. Ammo in one Clip",target.maxAmmo);
     target.clipLeft = EditorGUI.FloatField(Rect(0,120,250,15),"Ammo Left in Current Clip",target.clipLeft);
     target.maxClips = EditorGUI.FloatField(Rect(0,140,250,15),"Ammo Left in Current Clip",target.maxClips);

and how can i resize the float field because the full text isn't visible. thx!