I recently bought a new BLR lightweight in a 243. What should a person do for breaking it in???? As well, I'm looking for some feedback from some of you really experienced handloaders as far as speed??? I have been loading some 85 gr HPBT Sierra Matchkings, loving them. But I was thinking of trying to load up something 55-65 grains. I'm wondering at what muzzle velocity would I be risking burn out the barrel???