"Even with the lightest possible semi it will be a pig to carry around."
Not really, it will depend on the barrel profile and composition. I would carry a Remington 7400 in the field without any problem, not so with my Bushmaster Varminteer both are semi-autos. Both are designed for different applications.
Apples to oranges, apples to oranges. The same with bolt to semi, apples to oranges. Different tools, different applications.
Jim
For Yotes
For deer
For ground hogs or benchrest matches: