Thanks to all for your time.
My curiosity got the best of me and I did a little exercise/experiment to see what kind of answer it might give me. As the pictures show, I chose 20 fired cases at random, measured the length of each and recorded it on a post-it note, then sized the case and measured it again.
Every case, with one exception, stretched from .007 to .008(the exception stretched .009). This is the answer to my question. For those who didn't think that straight-wall pistol cases stretched, I don't know what to tell you. My dial caliper, though not top of the line, I've found to be accurate whenever I've used it.
I was struck somewhat by the consistency of the stretch, since one or two of you mentioned that there would be a large variation, which I expected also. All but one were within .001 of each other.
I discovered that the variation in length between unsized cases, with one exception, was only .003 or less. Seventeen of those were within .002 of each other. I was mistaken in my initial post indicating that there was significant variation in the case lengths. All, however, are at least .007 to .010 short of standard .44mag length, after resizing.
Some are wondering the rhyme and reason behind my question(and this little experiment). It's virtually impossible to adequately explain, but trimming cases after resizing, in my particular setup, is somewhat problematic and definitely inconvenient. There are ways around the issue, but none are very satisfactory in my estimation. I realize that trimming after sizing is the better, and standard way of doing it.
Fortunately, given the surprising consistency of case lengths both before and after sizing has convinced me not to trim the cases. A couple thousandths or so won't cause any problem with crimp. I will be chamfering and reaming the case mouths, which I didn't do when they were new; and this caused some rough travel thru the sizing die and a little difficulty seating the bullets.
Thanks again, friends. Hope this post was reasonably clear.
Regards,
Andy
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