When you take it apart, you alter the configuration of the
sights to the gun. If you didn't resight it in, it won't shot
anywhere near the right place. However, it should be consistently
off; firing "all over" means you might have damaged something in
the barrle. Take it apart again, clean it carefully and thoroughly,
and inspect all parts of the weapon that you can. Reassemble,
resight and test. If it still doesn't shoot straight, take it to a
gunsmith.