Mike;
First & foremost I am not trying to convince anyone that this is So "Because I said So". no indeed, in fact if only my meager evidence were available I would never even have posted on it. What I am saying is the evidence is out there, one simpy has to seek it out. My meager checking simply DID, fall exactly in line with available published data. As to the difference in a 26" barrel & a 30" barrel, not having a Parker at the present time I will fall back to the LC Smith data I posted earlier. Breech spacing was 1.156" with muzzle @ .8175". With barrels set "Straight" & distance between the projected axis of the two bores at 40 yds was 15.431"
For a comparision lets use those exact same dimensions "Except" for a 26" barrel. Convergence from breech to muzzle is still .3385" (1.156-.8175") .3385/26" = .01301923" convergence per inch as opposed to .011283333" for a 30" barrel. Multiplying this by 40 Yds x 36" per yard 18.748". Subtract from this the .8175" from which they started in the opposite direction gives 17.930" or a "WHOPPING" 2.477" difference Re the difference in barrel length only & this is at 40 yds for the total spacing between the two barrels. Error from point of aim would be half that. Also of course this does not give the exact point that gun is going to center its load in firing, but is simply the mathematical extension of the bore axis from a static position. That is where the bores are pointing "Before" the triggers are pulled.
This is all "Hard & Fast DATA, not worked out by me but by Gunmakers, simpy cited by me. Still looking for anything at all from your end other than Pure Speculation & Hear-Say.
