Hi Robert, sounds like you've got a handle on it! Consistancy of 243AI o.a.l. is excellent. The shrinking on fire forming is very close to what I get on my 6mm rem. AI . I fireform with full power loads ( one charge weight below max) and light bullets. I've used cream of wheat topped with Crisco and pistol powders, don't care for the mess personally. ---- On your 22/250AI did you use 250 Savage brass by any chance? What method did you use for fire forming 22/250 AI vs 243 AI ? Thumbs up on the imperial die wax. The idea never occured to me. Thanks, Dale