Pressure diff from choke?

[LBL]

Today I took a handful of my new 16ga skeet loads to the club and did test shots at the pattern board and using the club’s chronometer. I tested using my 16ga VHE though it’s not choked for skeet because I don’t shoot untested loads in my DHE which is choked Skeet/Skeet. Generally AOK achieving the lower speed (lower pressure) range I was seeking. The really interesting and unexpected result was the difference between the two barrels of the VHE. The RH barrel with Mod choke clocked 1040-1060 fps (4 shots). The LH barrel with Full choke clocked 1140-1160 fps! (3 shots)

If you have insight on this pressure difference due to choke I'd sure like to learn about this topic. For example: Is choke a factor to take into account with reloading (or any shot shell decision) when trying to limit the pressure that a Parker is subjected to? Or is this increase in fps with the full choke barrel just a manifestation of the same pressure going through a narrower orifice? If that’s true then one wonders why this “choke effect” on fps isn't highlighted, and what choke is used for all the fps specifications for ammo and reloading recipes?!?!


Thanks!