I have a Benelli SBE II Performance Shop Waterfowl shotgun, they come with chokes from Rob Roberts, lately my chokes have been shooting loose more than they did in the past so I reached out to the guys at Rob Roberts....and got this response for what to do.
I think I'll try a bit of anti-seize grease first....
Response from Rob Roberts Customer Support/Sales - web contact form
I think I'll try a bit of anti-seize grease first....
Response from Rob Roberts Customer Support/Sales - web contact form
--------- Forwarded message ---------
From: <sales@robrobertsgunworks.com>
Date: Tue, 23 May 2017 at 13:58
Subject: Re: Form Submission - Contact Us - SBE II Performance Shop - Chokes Shooting Loose
Rob,
It is very common for the chokes to loosen up after a few rounds. It has
to do with the tolerance difference between the barrel and the chokes.
We build our chokes within 1 thousandths of factory specs but factory
can vary up too 5 thousandths. My personal gun was the same way and I
went to the middle of the threads in my barrel and made a dent about
middle ways in the threads. Not a huge dent to where you can't screw the
choke back in but just enough it has some resistances so you wont have
the problem of chokes coming loose so often.
Jonathan Craig