Why do SXS barrel bore diamiters vary?

[Big Friend Ten (BFT)]

Originally Posted by will evans

I would think the balance point would be moved back toward the stock if one or more barrels had been back bored.

Will,
Removal of a few thousands from the bores will lighten a gun by a surprizing small amount. Chances are that the balance would not noticably change.
Mark

[Dean Romig]

Originally Posted by Mark Ouellette

Chances are that the balance would not noticably change.
Mark

And if Parker Bros bored a barrel oversize or back bored it and the gun no longer balanced and felt as it should, I'm pretty sure they would have invisibly remedied the situation. Of course we can't say as much for an aftermarket back boring job by someone other than the factory.

[Bill Murphy]

When gun shopping, I would rather be equipped with a bore micrometer than a scale. A smallbore Parker with .010 variation in bore diameter from left to right has been screwed with, end of story.