I'm new to this. Just tried an undertaker choke and my pattern is going very low. I'm using 3" Winchester copper plated #5'surkey loads. The pattern is about 6" low. My buddy says I'n not flinching or dropping the barrel when I squeeze the trigger. I seem to need to ain above the target to get the pattern in the head and neck. I came home undid the choke and put a mini mag light in the barrel shined it on the wall and my ain is good? any ideas?