Re: New Brass, .243 Cracked neck
The other concern with annealing is that you will cook the zinc out of the brass, thus destroying the alloy. Zinc is also toxic when inhaled. LDBennet's description on annealing technique is apt, but I've gotten good results using just that procedure. I have seen group sizes shrink, mainly (I believe) to more even neck tension on the projectile. The human eye is amazingly accurate, and I do my annealing in a darkened room to witness the color change during heating.
One has to weigh the gains versus the risks when handloading. However; if one is careful it is certainly not hard to do. Only you can decide if it's worth it to you.
Life's too short to shoot an ugly gun.....