Analyzing misses

Got out for another hour or so this afternoon to shoot some 100 yard targets with the Maynard. Here is the best of the bunch:


Don't know what to make of that group of four that fell into the seven and six rings. I have a shot string chart pulled from somewhere off the net, I think originally from an army shooting manual. Here's what it says:

click to enlarge

What do any of you think? jerking the trigger is a definite possibility, but the idea of having too large a peep near the eye (6 o'clock string) is also possible. I'm still trying to figure out the optimal place to cheek the gun for a consistent look through the peep. thoughts??