Hammergun - Thanks for your input.

I am pretty sure, too, that there is not some mandated universal standard written down somewhere. Also, I would expect a customer can request a minimum POIs deviation that the maker then meets in only the highest-end custom shotguns.

I would expect the issue of barrel regulation is treated differently in double rifles than double shotguns. I am just wondering about double shotguns.

In the case of non-custom double shotguns, I am thinking each manufacturer has a barrel regulation standard they generally aim for. Such information I am sure is confidential, however.

I am just trying to determine the general consensus of the cut-off between what POIs deviation is acceptable versus too much in a high quality mass produced double shotgun? In other words, how much deviation should a shotgun shooter tolerate?

--shinbone