Question for smarter people then me.
Not sure how it relates to shotgun chambers, but when I reloaded rifle rounds (and I reloaded a lot years ago). The more chamber pressure generated directly meant more speed for the round headed downrange. Any powder you looked at in your reloading books had a correlating x amount of powder provides this speed and x plus amount of that same powder gave more speed, but with increasing amounts of pressure. What some folks did was look at the maximum speed one could achieve (because folks were speed driven) at a certain pressure to speed ratio and then back off a grain or two and check for flattened primers, sticky bolts etc., which would show you were generating too much pressure. Folks also figured out if you happened to load rifle rounds that were too long and they touched the grooves of the barrel, pressure would spike big time. There had to be a bit of distance to where the bullet started to accelerate before it hit the rifling.
What I don't know is if 2 3/4" shells are fired in a 2 1/2" chamber does the opening of the crimp hit the shorter chambers and thereby cause increased pressure? I think from what I've read it does indeed.
What I don't know is if that increased pressure results in additional speed for the shot charge headed out the barrel? More speed, more recoil even though the shell is essentially the same, but simply fired in a shorter chamber?
Be curious what folks think?
Has anyone chronographed the same 2 3/4" load fired in a shotgun with shorter chambers and longer chambers and seen what the results are from a velocity standpoint?
