Small sprites become invisible or change shape (become blurry ) when moved

If I move the small sprites ( in this case I moved them along the x-axis ) slightly they get blurry or change the shape as seen in the pics I need to have these small sprites as bullets in my game. Sometimes these sprites become invisible when moved slightly but are visible in the scene view.

I tried sorting layers, I even tried importing different sprites ( some slightly larger ) I even tried with a clean new project. what could be the problem? thanks :)