Re: annealing and neck tension
CST, it seems maybe you're overheating your annealded cases.
If you can bend an annealed neck with a thumbnail it is too soft! IF you have annealed/heated until you saw a red glow in a lighted room you've gone WAY overboard. Such necks will be dead soft and have little or no springback at all; that's usually bad for accuracy! And there is no way to get it back, we can't even work harden it enough to make any significant difference.
You know brass is a mixture of copper and zinc, right? Zink is a fairly hard metal but it's brittle. Copper isn't brittle but it's too soft for cases. Mixed correctly they become strong enough to hold the pressures, mallable enough to be easily shaped into cases and has enough hardness to provide a little elasticity, called springback. Springback allows case necks to hold bullets firmly AND to contract after firing so we can withdraw the empties easily. Excessive heating (red hot) burns zinc out of the alloy, leaving what is basically a soft copper neck with little or no springback.
Metalergists broadly catagorize brass as "hard", "half-hard" and "soft"; each depends on both the alloy AND its crystal structure. Case bodies are and should remain "hard" but the forward parts need to be "half-hard". Working the necks with firing/sizing changes the grain structure by moving the half-hard crystals towards hard. Hard brass is strong and has lots of springback but it soon splits so over worked necks won't last long without annealing. PROPER annealing will change the metal's crystalin structure back to half-hard and that's as far as we should go.
Neck annealing is a bit like shooting skeet; it's easy to do but it's much easier to miss the target!
