To move the point of impact, the sights (either one, front or rear) can be drifted to compensate for any error in point of impact.
* The front sight would be moved in the direction the bullet hit away from the point of aim (i.e., if the bullets hit to the left, and you are going to adjust point of impact by moving the front sight, move the front sight to the left).
* The rear sight would be moved in the direction you want the bullet to move(i.e., if the bullet hit to the left, you move the rear sight to the right, the direction you want the bullet to move).
* To raise point of impact, raise the rear sight, lower the rear sight to lower point of impact, etc.
The chamber may be dirty and cruddy after sitting for that long. Go ahead and clean the whole rifle, then see if the ejection issue persists. If so, take it to a gunsmith for a once-over. Parts for that rifle are hard to come by, and may have to be made.