Originally Posted by phorwath
I'll measure the case lengths of some of my fire-formed brass and add to this post, providing some case length data. I'm not aware that a shorter case neck will substantially degrade accuracy, provided all the cases are trimmed to the same length. There's plenty of case neck length to hold the bullets securely in the case.
OK, I measured about 14 of the fire-formed cases. The vary from 2.455" to 2.483", with most of them between 2.460" and 2.470" in length. I have not trimmed these to a uniform case length yet.
Also, some of these cases were fire-formed by another individual. If you don't have a bullet firmly held in the neck and jammed into the lands when you're fire-forming, the case length can grow because the case head may not be firmly held against the face of the bolt when the firing pin strikes the primer. I'd guess the ones I fire-formed are more in the 2.455" to 2.465" in case length, after fire-forming but before trimming to a uniform case length. Hope this helps you decide if you want to go this route or not.