10 round CF magazines?

[groaner71]

I have an FCP-K in .223 and was wondering if there are any high capacity mags available without changing the bottom metal. It is a CF DBM.

[Cserv]

I know of a guy who makes and sells them for. 308's and other larger calibers, but don't know about 223. He goes by z71rat and call them ratmags. His work has lots of happy customers. They work with the factory set up.
Eric