Your deed may state a reference to a roadway but more often than not it won't, especially in newer deeds. I've read literally thousands and can't recall one stating to the center of a roadway unless it was just to make a description more clear. What it will state is a specific description of a property line that will in fact be the center of the roadway.
To get ROW dimensions you have to go back to the ROW deed/grant itself. What is written on your deed can be and is often wrong, but the detail of ROWs are covenants running with the land so it doesn't have to be stated in each deed. Legal descriptions don't change generally, but they certainly can if it's resurveyed.
You are correct that you own to the center of the road. And it could be that you are thinking of many people not knowing that back in the day and they screw up their legal description by leaving that part out because they didn't think they owned the road when they sold their place. I have seen that fairly often.
To the thread, ROWs are pretty standard in size but there's no concrete width defined by statute in Oklahoma that I'm aware of. The ROW width for interstates are not the same as for county roads or state highways, and city roads are generally different than those. You also get differences due to terrain or obstacles on occasion.
