need advice on shortening and choking a mossy 12ga

I am hoping to learn some things here. A good buddy at work is a turkey shooter and he asked me to cut and rechoke a mossy 28" vent rib barrel.

Been thinking and planning for a couple days not to jump in too quick and while measuring I found the barrel thicker at the end around the present choke .985". Barrel OD thins back to .945 at the 18.5" mark. The choke OD is .874 which would leave a difference of .037" per side instead of .055" now. I am thinking I don't what this risk of catastrophic damage. Wanting to help my friend I search for a 18.5 mossy with choke and vent rib but cannot find that combination.

Any advice concerning choke fundamentals, or if this combination is made? Have you ever done this? Is my concern unfounded. Dont know how to measure the strength from this type of force.

Thank you, Steve a

Locate a gunsmith that installs screw-in chokes regularly. By paying for his time and material, you will have a good turkey gun and save a friend. Not to mention the time and material you might have wasted. Regards, Clark

I agree. Theres some good shotgun guys out there who know what they're doing. I build rifles but was in the same situation at one time when I got into 3 gun and decided against it just from talking to them. Wasn't going for 18" but it still wasn't enough meat to work with. Good luck.

Edit-wasnt.... Was going for a 22" from a 26"