I have been shooting my dad's Mossy 500 for the past few months. We both shoot trap on the weekends, and so far we have put about 1000 rounds through it. We patterned it a few weeks after we got it. During patterning, we used Winchester AA Light Target 8 shot, and full, modified, and imp. cyl chokes. In all three, it shot a pattern of about 60% on top, 40% on bottom -- they only varied in core density. But now, it patters extremely high. We shot 35 yards (with the mid bead centered on the front bead, same as the first time we patterned), and the beads both centered on the target. But this time, it patterned very close to 90% on top, and 10% on bottom!! Ah! The only thing that was different from the first time we patterned was we used AA *heavy* target loads. What is going on?! You can imagine how frustrating this is... We do reload by the way. Can you recommend a way to somehow get the pattern lower?
Hueco
Hueco