Thanks for reply and I do realise that many of your posts are starting subjects to bring in other Q&A.

By specs I was meaning whatever parameters one has set for their gun or perhaps what the original regulation target may have been, if there was one.

I did notice when at the old shooting range in Ferlach, as a guest with Scheiring gunmakers, that there were blowers set up over the gun racks which would cool barrels, when stacked with their actions open. Much of the shooting I saw on the day was regulating and working up loads for new guns being produced by the many gunsmiths in this famous little Austrian town. Our visit was to pick up and try out a new 20G/7x65R gun that my German friend had made, specially regulated for 20G Brenneke slugs. We visited other gunsmiths while there and saw some magnificent lock work and engraving on double rifles and the like.