Call the park office first and get permission. Park managers in Oklahoma State Parks have authority to give you permission to detect. Generally they will direct you to the more primitive areas. They will have to take into consideration the historical context of the area. Also keep in mind that Lake Murray is the 'darling' of the state legislature so you might run into obstacles since you're not from around there. (The 'good ole boy' system is rampant in Oklahoma, particularly in state government areas, feel free to tell them I said this. Or that I'm still sayin this) Also, offer to clean up any trash you find, as parks are always short handed on help and they might appreciate this. I worked for OT&RD for 7 years, and never once had a problem with detectorists, as I understood them. Best of luck to you!
Well it rained allot while we were there and when it wasn't raining we were playing at something else. I did manage to get it the woods after some raining and there was no wind, 100% humidity and it was not good for hunting. Or at least not good for me to be hunting. May go back next year. Need to do some more research. I expected to only be able to hunt beach areas and such, but as long as you fill in your holes I think most all of the public land is open. A few of the high traffic areas were off limits.
Well, that's Oklahoma Smokin Cache and lucky you, it finally got hot so you probably didn't have to put up with chiggers at least. I don't know about Lake Murray, since it's older, but every state park in Oklahoma had an archaeological survey done prior to construction. These surveys were published and list every historic and pre-historic site found or known to be within the proposed park boundaries, and list their legal location. Maybe not every park, but particularly the ones associated with BLM lands did. These list old home places, Indian camp sites or areas of activity, and other areas of historical note. I'm not sure how you can come across one (maybe call the Oklahoma Archaeological Survey? Ask for Richard Drass.) I have one for a few parks in western and southwestern Oklahoma. I used mine in attempting to nail down a purported location of a lesser known 7th Cavalry camp from 1868 along the Wash*ta River in Oklahoma. Due to 9/11, and the location, I could only stand a 1/2 mile away and look thru cheap binoculars. I was confronted real quick by overzealous law enforcement and ordered to leave the area. I pointed out I hadn't crossed nor displayed any intention to cross their damn fence, and was an American citizen, but they had bigger guns so I left. Good huntin, and plan a trip to Oklahoma in October or so. You might like it better, but they could have freezing rain.