The Second Amendment exists because the founders wanted their nation to have no standing army whatsoever. They wanted to be a nation with nothing but a militia to avoid the burdens the British standing army inflicted upon them even in peacetime. Washington argued against this but it wasn't until the Battle of the Wabash where nearly 1000 militia members were lost to a similarly sized Native American force who suffered only about 60 casualties that they realized they needed actual soldiery. After this the Second Amendment became vestigial.

I'm not against guns or gun ownership in general, but I absolutely hate people trying to say all the founders believed it was our "god given right" to own firearms. That's not what the Second Amendment is about and the only people who think so are those who don't know their history.

Also repeating weaponry existed in theory in mechanical circles at the time but no one made anything close to resembling a practical weapon for quite a while. It would have only been on the radar of men like Franklin or Jefferson who dabbled in that sort of thing. They were still using cartridge reload weapons up to the civil war half a century later. A lot of repeating weaponry was perfected during that war as the two sides tried to one up each other.

So no, the founders didn't see the coming of repeating weaponry and embrace their citizens having unfettered access to it.