On the autobahn people go way faster than 100mph. 20 years ago 200+ km per hour was not uncommon. That's something like 150mph! Now there's more traffic, so a more common speed is 160-180, which is still substantially more than 100mph. Long live Germany!
Ahhhhhh....the .308. Let's compromise. Carry a bolt-action, long barrel, high-power scope mounted .308 for snipery stuff, and a lighter-powered assault rife for when you need fast action.