Royalty Interest on Lands for which Production has and continues to occur

My Grandfather had a 1/48th Royalty on 420.5 acres and a 1/24th royalty on 266.5 acres, both in Abstract 164, W. J. Eaton Survey, Victoria County, Texas.

In looking at the RRC map, it appears that there are a number of wells, some still producing for which we, as direct named beneficiaries, have not been paid to lease or for production.

What steps should I take to capture what is rightfully ours and due to the size what is the most economical way to handle this?

Did he have a Royalty or did he own Minerals? There is a huge distinction. If you're not sure, you should engage the services of a Landman to help you sort things out.