[quote=Marc Stokeld]so if a gun has no gap does it shoot loose quicker (if so, how much quicker) or do you risk cracking the action at the action flat/standing breech angle?

what is the remedy?[/quote

It will depend on the gun ,how much gap is needed and the condition/reason the gap has gone . There is no one size fits all answer other than some re-joining will probably be needed. This may involve new joint pins or welding up the hook or it could be as simple as filing a couple of thousands off the flats of the barrel and or action as has been the case with some new O/Us that have not been freed off correctly and are hard on the bite because the barrel wings are hard down on to the action .