Biggest change is a new stock. But the severity of the split changes with seating depth. All groups are worse since the swap but not all are split like this. It’s like when it tightens up it splits into two tight groups. Any ideas?
I had a similar issue after putting my rem 700 in a stockys. It drove me nuts for a year. I finally took it to a gunsmith and he found the pillars were loose in the stock. You couldn't tell by looking at it. Only once he drilled them out could you see how bad it was. He installed new pillars, rebedded, and it shoots great. He was convinced it was a bedding issue, I didn't think that was possible until he repaired the stock.