Background: This is for information only. There is a shortage of .25-20 WCF brass and neither W-W or R-P will answer queries as to planned production. Having some extra W-W .218 Bee cases, I first tried ti size up these and split some necks.
Next step was to size .32-20 cases down. Trying to size my last lot of .32-20 Starline, I lost seven of the first ten cases when they collapsed folding inward. I then talked to Starline while at the CBA Nationals about annealing.
Buying the Anneal-Rite setup, I worked a ten cartridge sample running them six seconds in the flame to bright cherry. Three of the cases collapsed; one on the shoulder and two folding inward. Running the next ten-case sample four seconds in the flame just to dull cherry, no cases collapsed. Another ten-case sample achieved the same result..
I then run 310 cases using the four-second dwell in the flame. I lost a total of fifteen cases by collapsing. Slight resistance when sizing and a dab of Imperial Sizing Wax works well. There are now enough cases to shoot a Regional or National Match weekend.
The lesson is to experiment, the dull cherry works far better than bright cherry.
Farm boy from Western Illinois, living in the Magical Pacific Northwest