What made the attack by this Jew-hating nut, Robert Bowers, so lethal (11 dead, 6 wounded) was that his guns had two features. Both features together had to be combined in order for his attack to be so devastating; either feature alone would not mean much.
Feature 1: Semi-auto operation. Once the guns were loaded and cocked they could be fired over and over again just by pulling the trigger. No pumping, no manual cocking, no working of any levers. Just point and click, like your mouse.
Feature 2: Full capacity magazines. I read three news articles about the shooting, and I don't know exactly what the magazine sizes were for the exact weapons he had, but generally AR- 15 rifles use 30 round magazines as standard. Glock pistols use 15 to 17 round magazines (and he had multiple pistols). These guns all used detachable magazines that could easily be discarded when empty and replaced with a fully loaded fresh magazine. This is quite a bit different system from a tubular magazine system which is slow to load or reload.
But, I think we should ask ourselves this question: if the crazy killer had been limited to purchasing only 2 firearms--let's say one rifle and one pistol-- and these weapons were not semi automatic (let's say the rifle was a pump action and the pistol an 8-shot revolver) and if the rifle had limited capacity magazines that held only 10 rounds each...
...could he have still killed many people in the synagogue ? Using that one pump -action rifle, with a few extra 10 round magazines stuffed in his pockets, and one eight shot revolver? I think the answer is yes, he could've killed several innocent victims.
The only real difference is he would not have been so dangerous to the responding law enforcement officers after he killed the worshippers. He would've been shot down immediately upon engaging the police rather than matching their firepower with his and having a long drawn-out gun fight with the cops that resulted in two of them getting seriously injured.
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