Cat,
Were they printing high or low, and did you let the barrels cool for 20-30 minutes between shots?
I have a trick for cooling them that costs a bit, but it speeds up sighting in. I take the warmed barrels off and the forend off, then I spray them with starting fluid outside.
Warm/hot combo gun barrels tell you only to what extent they wander when warm, and it can be a lot.
I'm real interested in your patched bullet results and welcome more results.