Per another thread, Ed Huntress reminded me that the Australian Cadet version of the Martini action was a superb action for a .22 target rifle. Since they were at one time very common in the UK and Oz, any chance any of them are still available? Just the action would be fine.
Gunner
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote!" -- Ben Franklin