What is the difference between the 2? Everything I read about savage people say its easy for the average Joe to rebarrel. Everything I read about Remington 700 people say "have a qualified gunsmith perform a rebarrel". Can you help explain why this is? I was able to find a video on the savage, but I've tried searching a bunch on remington and keep seeing the gunsmith thing. Thanks!

Because the savage uses a barrel nut that allows the barrel to be infinitely adjusted in and out to set headspace. Whereas the Rem barrel has a shoulder on it which makes the barrel stop in one place; headspace being set by reaming the chamber deeper, or less deep. That is why anyone can fit a savage barrel, but it takes a lathe, reamer, and gauges to fit Rems and others.

Thank you.

There are a couple of manufacturers at least that offer barrels for Remington 700's that have the Savage type lock nut for headspace.

Yep and plenty that eliminate the Savage lock nut and butt the barrel on a shoulder.