I think we all did learn something about this when the teacher’s back was turned, long ago, with a straw and little wads of paper we took out of our mouths.
My recollection is that when inhaling as deeply as possible and expelling insanely hard to the verge of bursting a blood vessel, “it” either leaves the straw faster the tighter it fit, or not at all, in which case you see stars and damaged your body.
There is such a thing a cone barrel .22’s where the LR lead .22 become a .177, exited faster, and was more accurate. I don’t think they were easy to make, and may have had other side issues like fouling, but they were a real “thing” and they would seem to confirm that in at least some cartridges a tight bore equals higher velocity.
I will say that my brass and bullet jackets have paid a price for that “benefit” when I have had them. But they were extremely accurate and I downloaded to offset the problems once I figured it out.
