im a noob and i got in to a hell of a task. i opened my gearbox to change the spring. im a mecanic so i told my self o could do it eaven if alot people told me not to touch it. anyways. i took it apart and put it back together. but now it shoot out the bb 1 time out of 3 and it shoot veeery slow. anyone can tell me what could be the problem?