Can chokes be opened by shooting over many years?

[Tom Flanigan]

I never thought that the degree of constriction could be lessened by shooting. However, I just restored a Trojan that was owned by my uncle. He bought the gun in 1921 new. He used it hard over many years on ducks and pheasants. The checkering was just about worn off. He took care of the gun but just about all of the original finish was missing. He ordered the gun with modified and full chokes. I know for a fact that he never altered the gun in any way. I am the second ownert of this gun.

My dillema is that the right barrel is now almost cylinder. The left barrel is about improved modified. Barring a mistake at the factory, it would appear that the chokes were opened by many years of shooting. I never thought this possible. But now I am questioning my thoughts.