Advise on use of poly-choke. I am familiar with only one design of a "poly-choke". Ifthis is what you have on your shot gun,you can screw the choke collar completely off the assembly, revealing a tulip like, multi-finger contraption that seves as the adustable choke restrictor. As the choke collar is moved it applies pressure to these fingers, forcing them closer togetehr as the choke approaches "full". However, there is still a small groove between the tulip fingers, which is wider at the more towards "open" setting. This design poly-choke can strip a small amount of plastic from a shot-cup as the cup passes over the"tulip". These shreads can beocme lodged in the groove that is between each "petal" of the adjustable choke. I would recommend that you check this choke now for such shredding. And I would also suggest that you periodically check for this. Significant build up can interfere with shot strings and probably can somewhat raise the pressure if the amount of plastic jammed into the grooves becomes significant.Frankly, I would have a gun smith remove the poly-choke and add a modern choke tube system.