Briley could jug choke the gun, they remove a little metal just prior to the muzzle to get some constriction.

I'm getting old enough that I don't worry too much about resale on the guns I actually use. It'll be someones else's problem. But, I think if there was going to be a tube in the gun anyway, I'd rather have the option of changing the tube, rather than having it permanent.

Good luck.

Best,
Ted