I have removed several T3 barrels. Some were easy and some were difficult. It was a learning process for me. The weak link always seems to be the barrel vise. I had the Viper, but the vise contour was straight while the Tikka barrel had a slight contour. This resulted in very little actual contact or 'purchase' on the barrel so it would spin. At the time, there were no aluminum Tikka contoured sleeves, so I made my own using epoxy. This substantially increased my purchase on the barrel (also used drywall tape). Some barrels (mostly magnums) were installed with an incredible amount of pressure at the shoulder/action face. I initially used an internal action wrench, but found there was a greater chance of actually twisting the action itself. I eventually switched over to an external, flat sided action wrench with a breaker bar and a large mallet to jar them loose. If the don't move by the third hit, I resort to heating up the action surrounding the tennons and try again. That always seems to get it done.