Neck sized rounds in different barrels

[Treebone]

Excessive head space is not the cause of case separation, it causes excessive recoil as the case slams against the face of the bolt, (or breech face).

Case separation is caused by the pressures generated inside the case which cause the brass to flow forward as though it is being extruded. This is what stretches the case and why they have to be trimmed back to length.

Disagree enfield, when an excessive headspace condition exists the sized case is driven forward by the firing pin untill it butts up against the shoulder, then upon ignition the case flows backwards towards the bolt face.
Continuous sizing and firing leads to thinning of the web area ultimately leading to case haed seperation.

Ian.

[tacfoley]

Disagree enfield, when an excessive headspace condition exists the sized case is driven forward by the firing pin untill it butts up against the shoulder, then upon ignition the case flows backwards towards the bolt face.
Continuous sizing and firing leads to thinning of the web area ultimately leading to case haed seperation.

Ian.

True.

tac, reloader since 1965.

[bewsh]

phew...some doozies here

excessive headspace from an oversized chamber
and pushing the shoulders back too far result in....
the SAME THING

too much space/flow/stretch - symptoms could be all manner of things from light strikes, dented shoulders/bodies, primers popping, case webbing thinning/head separation

never have I heard that it causes "excessive recoil"....

If your FL sized brass doesn't fit ANY rifle either the die is not in spec or the chamber is not in spec
there are lots of specs and depending on the monkey using the lather and reamer you could be over or under spec producing a tight or slack chamber

its why some rifle makers will produce dies specific to THAT chamber

I have (access to) four .270's
neck sized brass from one gun fits into two of the other but not in the reverse direction
one won't accept anything fireformed in the other three
4 chamber sizes in two Parker Hales and Mauser and a BSA