Did some trading and now I am owner of Maynard rifle with four extra barrels. It is wearing a 22 Extra Long in the "modern" 1882 style cartridge. The other barrels are various 35 and 40 caliber in the older thick rimmed cases. A couple of the bores are very nice a couple are not so hot.

Now I need to decide if it is time to begin investing in blackpowder shooting with the Maynard or just stay in my modern comfort zone.

Anyone have any experience with the Maynard? Tips or worries?

You are very fortunate to have found a Maynard with all those barrels. I have owned and shot two Maynard Second Model percussion carbines and one .38-50 Maynard cartridge rifle that I did not shoot, but wish I had.
I recommend you get a copy of "The Breech Loading Single-Shot Rifle" by Ned Roberts to start with. The Maynards won many medals and many glasses of beer back in the golden era of Schuetzen because of their excellent workmanship and fine barrels. I would certainly consider consulting with Robert Hoyt of the Freischutz Shop in Pennsylvania regarding reboring the damaged barrels if the bores are too far gone.
You can get cases and appropriate molds from Buffalo Arms in Sand Point Idaho. There are a lot of single -shot fanatics out there who would dearly love to be faced with your quandary. Good luck!

Absolutely beautiful! Quite the find.

Looks like I have some homework to do; thanks for the reading list. A couple of the barrels could use a re-bore or sleeving. It will take me a while to get to the point that I'm shooting this one.

Thanks again,
Charlie