doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Problem: O/U Barrel Regulation

Vangulil –

You raise some interesting points. Specifically, which manufacturers make the best regulated shotguns? And, if there is a problem with barrel regulation, which manufacturers fully rectify the problem immediately? Based on my experience, obviously B. Rizzini does not perform well with respect to either question.

But, in this odyssey of mine I have spoken with a great number of personal acquaintances, gunsmithing concerns and shotgun manufacturers on the subject of shotgun barrel regulation. These discussions have included gunsmithing enterprises which have worked on perfecting barrel regulation by choke modification for Olympic trials, as outlined in my previous postings on this topic. These concerns have seen guns from many different manufacturers. What I have learned is interesting and gives me some pause. So, for the benefit of those utilize this forum, let me provide some of the information obtained in this way.

First, none of the shotgun manufacturers seem to be immune to having barrel regulation problems in their products. This statement includes at least two of those companies you mentioned in your posting, directly above. Interesting what? However, based on several reports -- in very instance these two companies immediately rectified the problem. But, the assumption of responsibly and rectification of the problems by the manufacturers is not always the case – even with high priced guns. As reported in one of the postings, above, by AmarilloMike on this topic, his Beretta SO5 had a 7.2 inch point of impact divergence between barrels at 40 yards. Other postings report even worse results for some Grulla and Fabarm guns. In some of these cases it was reported or implied in the postings that the manufacturers claimed that the guns were “within specification”. If true, these are absolutely ridiculous assertions and are obviously contrived to avoid responsibility.

Only Browning is reported to have a published barrel regulation specification which they will guarantee. This point was mentioned in some of the above postings. I have not been able to find the point of impact guarantee information on the Browning website. But, based on personal conversations and the postings above, it seems that there may be two metrics associated with this specification:
1. The divergence between point of aim and point of impact for each barrel at 40 yards ( Reported as a maximum of 3 inches)The point of aim is probably defined with respect to the plane of the rib.
2.The divergence between the point of impact between barrels at 40 yards ( Reported as a maximum of 4 inches )

If you think about it, both metrics are required to properly define the point of impact performance for a double gun.

In speaking with several gunsmithing groups it appears that some modestly priced production guns perform better than others, re: barrel regulation. Notably, Browning and Beretta are reported to be better than average in this performance area – but, they are not immune to problems occurring. Much to my chagrin, B. Rizinni was reported to have significant problems.

Regards,

Don

All --

It occurs to me that the industry and [b]in particular, the buying public would be well served by the development of a set of industry standards by which the barrel regulation of double guns can be measured / defined. For this purpose method of measurement for the point of aim vs point of impact divergence should be defined or both barrels. In addition the method of measurement for the point of impact divergence between the two barrels should be similarly defined in such a standard. I can think of several simple methods for making these measurements.

The individual manufacturers could then publish their own specification for barrel regulation with respect to these standards, which they are willing to "stand behind" and guarantee. These specifications could provide a competitive advantage to technical competent companies. Even the unilateral adoption of such standards and specification could provide an individual company a competitive marketing advantage.

The current barrel regulation problems, found throughout the industry, appear to derive from the benign neglect of an uninformed public which assumes good barrel regulation as a given .... and from the not-so-benign neglect of most shotgun manufacturers. If the current situation is to change for the better, the buying public may well have to demand this new set of industry standards.

Unlikely? … well, I do not know. But, if a few companies adopt such standards and reasonable specifications, based on these standards .... and this fact is well advertized by those companies that adopt them -- the entire industry may be forced to move in this direction. The technically competent companies and the buying public will benefit from this process.

Regards,

Don

Probably the only way the situation would improve would be if enough shooters patterned their guns soon after purchase and publicized the results on sites like this one. Bad publicity might hurt sales enough to get manufacturers' attention. Rizzini has certainly lost sales to readers of this site.

Vangulil --

Agreed ......... Someone should take your suggestion and start a new topic in this forum which could be used to post the patterning, point-of-impact measurements made by the participants in the forum. Certain protocols would have too be established for the required measurements. But, it seems such an undertaking could cast some important sunlight on the subject and in so doing help everyone.

Any "takers" out there?

Best Regards,

Don