Thanks Tuner! Periodically I fire out the carry ammo in my very reliable 5" Springfield LW (ramped barrel, 18.5 recoil spring) to replace it with fresh. The last time the Cor-Bons did nosedives in 2 CMC 10x and 2 CMC 8x mags. This was fairly upsetting, but when the same mags refused to feed BALL, I was indeed unhappy but not panicked. Because of your very informative postings, the issues with all 4 mags were resolved with a call to Wolff GunSprings and 2 three-packs of their +5% mag springs. The 5" feeds any and all now and once again provides comfort and pleasure. The only unresolved issue is with a Springfield Champion I tried out today. Cor-Bons and ball both feed out of the SA mags and CMC 8x's, but still nosedive in the freshly sprung 10x's with this pistol. I don't see this as a major problem since the smaller mags function well. Could these nosedives be a result of the shorter recycle timing associated with the Champion? Thanks again for sharing your knowledge. You saved me $$ and frustration.