By my count the Tikka T3x action has three threaded pin locations to the aft and two to the fore that are tapped completely to the interior of the chamber. My question is for those using the UM rings, do the rings completely cover the exposed pin locations due to their width or are some exposed and prone to debris collection and potentially failing into the chamber? Is there an alternative to the 6-48 (?) plastic plugs (long gone) the rifle came with and if so what did you end up going with. Thanks for the help.