I have a Winchester Ranger 30-30 from the '80s, in excellent condition. I know it's nothing fancy or special. I bought it last year, and have taken it out a number of times, tried some different loads, jacketed and cast, with fixed sights and a scope. Some shoot better than others, but what they all have in common is vertical stringing. The typical 50 yard group measures an inch or less horizontally, and about 2 inches vertically. There's got to be something simple (I hope), but I'm missing it.