The rule was you had to use shells purchased when you paid your entry fee. They had to come from the shell house on the grounds. The rule changed only once to my knowledge. The shells were not marked. In later years the companies did make special runs for the Grand.
IF you ejected the hulls, they became the property of the club. Many trap clubs had this rule, but not all. The shells were sorted by the trap boys and sold to the club members for a nominal fee.
Back in the day, the saving of shells while shooting the trap line was considered a distraction. Most shooters used their ejectors in registered competition. Not all, as can be seen by watching the movie.
As far as automatics at trap, apparently you've never heard of the Remington 1100.
Many, many, very fine trap shooters used 1100's. In fact, that reasonably priced product did more to popularize the sport than any before or since. You had to carry spare parts, but you were in the game for a couple hundred bucks.
ATA blundered badly moving to Illinois. It is indefensible and unexplainable.
