I was escorted through the Shiloh Sharps plant in Big Timber, MT a few years back, and the adjacent Boulder Foundry as well.
Bob showed me the barrelmaking station, where they press a button through the barrels to make the rifling. This method also “proofs” the barrel, as the pressure will split the barrel if any flaws or seams exist in the metal stock. He had a couple of these failure around for illustration; better there a burst than when somebody is shooting it.
He handed me a smoothbore barrel, drilled and reamed and ready to rifle, and pointed out the choke that they put into them. With the lands and grooves missing, it was easy to see how the shadow lines converged (like long isosceles triangles) from breech to muzzle. The full length of the barrel; not just a “jug” or constriction at the end, like a shotgun choke or (as I read somewhere) the choke Pedersoli puts in the ends of their BPC barrels.
I asked Bob how they did that, and he said if he told me, he’d have to kill me.
So I sympathize with jLouis. I can only imagine the midnight ceremony, the sinister, hooded figures surrounding him, the weird, eldrich music in the background, the blood droplets on the holy card, the burning of the card held in his hands, with the oath, “May my soul burn forever as this card burns, if I ever divulge this barrelmaking secret. But, of course, I am free to tell everybody that I do know the secret, and say ‘neener, neener; nyah, nyah,’ when they ask me what it is.”
I have three Shiloh Sharps and one Pedersoli Sharps that a previous owner cut a couple inches (and presumably the choke) off the end of the barrel. They all shoot very well, but the Pedersoli tends to put the first shot high and left, out of a clean barrel, while this tendency is much less noticeable in the Shilohs. I’ve also had a lot less trouble working up paper-patched loads for the Shilohs; still working on the Pedersoli.
So if you can put a choke or a gain twist into a barrel, and it doesn’t hurt the accuracy or ease of loading, why not? It at least sounds logical, even if it might only gain you a point every ten (or a hundred) matches.