The 700 is a completely different animal than the model 600 (Automatic) See page 115 of the Benjamin book for a look at what the insides of a model 600 looks like. It is a true automatic with a clockwork trigger mechanism. Nothing else quite like it. Pump up the 600 with 2-3 strokes and you get 3-4 shots as fast as you can pull the trigger. Working examples of the 600 are extremely rare.
The model 700 is a only a self loader with no automatic action. The 700 and the model 720 are the same basic action with different pumps.
Another fascinating Benjamin model is the 710. See page 228 for a look at the 710. With the large air tank, a pretty unique feature, after pumping up, multiple shots can be made (no automatic action, though) without further pumping required. Very much like the old large bore airguns of the 1800s. The 710 came out in 1940 and was not made after the war, so, it is one of the rarest Benjamins.