Yes, they describe the various chokes.
* Full *- Improved Modified ** Modified **- Improved Cylinder **$ Skeet *** Cylinder Bore
No, Invector chokes will not fit the Browning Medalist shotgun. The Medalist typically uses fixed chokes that are integral to the barrel, while Invector chokes are designed for Browning shotguns with removable choke systems. It's important to check the specific model and choke compatibility for your shotgun.
By opening up or constricting.
Modified.
FullF0 (*) ISP(¹).Improved ModifieldIM00 (**) IISP(¹).ModifieldM000 (***) IIISP.Improved CylinderIC0000 (****) IIIISP.CylinderCLC0000 (C****) IIIIISP.Skeet(2)SKSK (Skeet Beretta)No NotchesSP
Chokes for shotguns shrink the bore's diameter to tighten the shot pattern and increase practical range.
M=MODIFIED IC=IMPROVED CYLINDER S=SKEET F=FULL Also, as stamped on receiver: * Full *- Improved Modified ** Modified **- Improved Cylinder **$ Skeet *** Cylinder Bore
they help with patterns of shot and accuracy of slugs
A good basic article on chokes http://www.ssaa.org.au/stories/shotguns-a-beginners-guide-to-shotgun-chokes.html
Refers to the amount of constriction at the muzzle.
Try e-gunparts.com
Herter's sold various maker's products with their name on them.