If this was purchased as a complete rifle from Rock River it should be marked .223 Wylde.
It will not be marked Wilson Arms.
There will also be a barrel code stamped on the barrel.
You can Google the barrel code for more info.
You will probably have to remove the handguard to see some of these marks.

Note:
Wilson Arms, a barrel maker, not to be confused with Wilson Combat, a gun maker.
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