It is a gun that has barrel wall thickness too thin. .021" and .022" The nearly same gun but in excellent barrel wall thickness of .028" and .032" and unmolested near pristine condition is listed for sale now here:
https://www.gmackinlay.com/product/12g-sidelock-ejector-by-joseph-lang-son-28-x-2-1-2-barrels/Compare what you see in this Lang gun versus what you see in the worn out Lang you have listed at Holt's and you will be educated---price education especially of several thousand dollars maybe arriving at your gun cabinet.
