I had a custom double made for me and part of the process was a "Fitting".
The dimensions of my perfect fit, English stock are 1 9/16 x 2 1/4 x 15 1/16.
I'm thinking of having another made but want to add a Vent Rib to the equation. What happens to my perfect dimensions now?

DAH and DAC are probably out the window.

Not to mention any dynamic fitting you may have done will be useless with the higher sighting plane.

If you don't premount, and don't stack beads, It could theoretically not matter, as you wouldn't be worried about looking down the rib anyway.

Imagine adding a 4" high trap rib to you current gun. What would you be looking at when you mounted your gun? Answer: A whole lotta rib. so, from that exaggerated example, some of your prior measurements won't be what you want with a different, higher, rib.

Why would there be any difference?

That's what I'm starting to think.
Wouldn't stock dimensions be measured off of the sighting plane?

Something like this Bob?

What about cast off/on ?

Dimensions should all be from the sighting plane, which is the top of the rib no matter if it's vented or not.

Having said that none of my SxS guns have vent ribs, my one O/U and one Auto gun have vent ribs as does my SB Trap gun. I guess because of the way they are configured, they need it to get up to proper sighting plane. I can't see any advantage to the vented rib on a traditional gun, in fact think it's unattractive on a SxS. But taste is individual and if you want a vent rib go for it. Don’t let fear of fit hold you back.

I will say if you have two guns from the same maker it's a big advantage if they are as alike as possible. Different chokes even different gauge or barrel length no problem, feel the same handling is to your advantage.

Boats

I can't stop looking at that contraption of a gun.

You want to shoot trap with the big dogs? You better bring a trap gun.

I don't think we can "unsee" that gun. However, there is a possibility that it can cure cataracts.

I wonder, did that guy build up his stock to match that very high sighting plane, or, did he build up the sighting plane to match the very high stock? Bet it was a nice field gun before all that "stuff" happened to it.

No eye protection? Hat orientation 180 degrees out?
Go figure!

Even more strange....does it not look like he is sighting down the lower rib?

The gun in question is rumored to be a Holland & Holland, which he can afford.
Google Saeed Al Maktoum 2010 ISSF World Cup, Italy

Yeah, I noticed that too. I put a straight-edge across that rib, or truss, or whatever it is, and it is lined up with his eyebrow. Maybe the real advantage to it is making your competitors giggle so much that they can't shoot well.

As Drew says, he can afford to do whatever he wants. As a billionaire member of Dubai's ruling family, he could use a Holland and Holland as a truck gun.

I think he just uses that gun to win gold medals with.


He probably has other shotguns to bird hunt with like an old Thomas Boss he keeps bouncing around in a gun rack mounted in his 1987 Ford F150.

Yes, well, he may well be a skeet shooter according to the ISSF strip on his jacket!
Mike