I put this same barrel (.243, 1-8, 28") on my rifle a couple of weeks ago. During the break in, the first 3 rounds made a single bug hole. Everything went south after that though. Found out the action had shifted in the stock and the whole right side of the barrel was against the barrel channel. Finished the break in with what rounds I had with me, (everything was still shooting 3/4" or less) took the rifle home and bedded the action. I hope to start my load development again this week end. I plan to try some 107gr. SMK’s and 105 Amax’s this time.