All mine is Winchester Super Match mid-range Wadcutter factory ammo that was once fired when I shot it in my PPC revolver. When I started in revolver competition again, I measured them to get an idea of varience for crimping. There was enough variance in this same headstamped, same lot ammo to convince me to trim them to a uniform length for a uniform roll crimp.I am using all range brass, so the lengths were quite varied, and I like nice consistent crimps, so I trim all sized .38 Spl cases to 1.140, even though I don't reload a lot of .38 Spl with roll crimps, which are more critical than taper crimps.
If the case length is varied how do you seat to the cannelure / crimping groove?
But if the case is at a minimum length isnt there a chance you miss the case all together? Or longer than expected and buckle the case? Thats what im not understanding.Since over half of the 8,000 to 10,000 rounds of .38 Specials I load for my wife and me each year will be fired through lever action rifles, I load for the OAL of 1.480". With cast bullets, it doesn't matter where the crimp groove is, since you just roll the crimp into the side of the bullet where it needs to be, as long as it doesn't end up in the lube groove. I've been doing it this way for well over half a century, and it works for me.
Hope this helps.
Fred