So I have inherited a savage model 11 in .223 and I am looking for any info about the twist rates and such. This is a heavy barrel rifle with the accutrigger.

I've tried looking it up on the website but haven't used the serial search yet... just wondering where to start looking to tinker with it.

Also, would this be a candidate to rebarrel for 6.5 Grendel?

Find your twist rate with a cleaning rod, a jag, and tight fitting patches.

To convert to Grendel you will need to modify or replace the bolt face, modify or obtain a different/modified magazine, and of course a barrel.

Hypothetically, if I was in your shoes and wanted to change it to 6.5 Grendel I would definitely do it. The rifle didn't cost you anything and its not too expensive for the additional parts.

I would:

Buy a new bolt face, possible sell the .223 online.
Buy new bottom metal with the correct magazine, probably CDI Precision
If its an accustock I'd keep it, if not I would replace it. Probably an unfinished Stockade.
Buy a new barrel, CBI makes drop in replacements and they shoot lights out.

Instead of inheriting a .223, you just built a semi-custom rig for under $1,000. Not bad at all!