I have been thinking about doing the same thing but with a Mauser that will never fire 8X57 again
or any other large Mauser round for that matter.
The chamber and cannon too rusty.
I have an Austrian Voere .22 insert / conversion kit that will convert 7 and 8 mm Mauser to .22lr
but I would like to stop it flexing when I shoot.
Was thinking about grease on the insert and putting silicon sealant down the cannon
to take up the slack, and hope that the grease will help removal when I want to take the Voere unit out.
Or would it be best to epoxy in and never take it out.?
I know I am talking about a Mauser but it is the idea and the principles of this topic.