Picked up a new Tikka Lite in .243 a few weeks ago and have been working up a load since using CCI primers, Remington brass and H4350 powder. I loaded up 5 rounds each of 37.5grs, 38grs., 38.5grs., 39.0grs. and 39.5grs. (40grs. was max). I only fired the first 15 rounds as the temps were in the mid 30's and I couldn't tell if the groups were bad or if it was me shaking from the cold. When I got back to the house and started cleaning the gun I noticed a small crevice in the bolt face. At first I thought it was a scratch but when checking the brass I found one that had burn marks around the primer. None of the brass felt overly loose when I installed the primers and they were installed by hand using one of the RCBS priming tools. I also way each load twice (once by beam scale and then by digital Dillon) so I'm almost positive that there wasn't any excessive load in this round. In over 20 years of reloading I've never had a bolt face damaged by gases coming from the primer and wondering if this could be caused by a loose primer or something else. The hole in the bolt face is about the size of a pin head wide and about 1/4 that deep. Should I look at replacing this bolt or is this more cosmetic damage? As always, appreciate your help.