André

Does your experience invalidate my thinking ? No and Yes !!!

I fully understand how doubles are regulated (ie made and then barrels regulated by
the methos you say).

I wouldn't say that it can "substantially improve barrel regulation".

Wha I would say (and did in my previous post) is reposted below:-

"I have a couple of Double rifles that shot WELL WITHIN ACCEPTABLE EXPECTATIONS
Once I had them shooting, I DECIDED TO PLAY with the Bullet seating depth that of course affects the COL.

I found that I could improve the accuracy even more of some of the Double Rifles."

What this meant is that instead of 1.5 - 2" apart, I found that some of the rifles came together
really close - 1". Nothing else changed.

I will comment however that I am NOT talking about 1 - 2 thou difference in bullet seating depth
but more like 4 - 6 thou - it partly depended on where the rifling started.

It obviously affected barrel time but I just found the "sweet spot" !!!

On the other hand, I hav other double rifles that shoot the same with 4 - 6 grains of powder
difference (500 Nitro's being a good example).

Hope this answers your question.

500 Nitro