Brass/dies issue or excessive headspace?

[A5BLASTER]

Guys,

Before we start looking at exotic reasons can we not look at the obvious first...His cases are stretching 0.012" each time. His ammunition is too small for the chamber; too much headspace.

And the most common reason for this is that the die is screwed in too far. Reloaders faithfully follow manufacturer instructions and screw the die in until it touches the shell plate. They end up with an arbitrary amount of case stretch that will never maximise the case life. The alternative is that manufacturers expect reloaders to understand headspace and own tools like comparators, which on this forum we take for granted. Screwing the die in till it touches the shell plate is OK for the majority of chambers that are reamed somewhere in the middle of SAAMI specs, but 'Sightedin' has a chamber machined on the generous side. His cases are stretching .012", Very similar to my Lilja group-buy barrel which is 0.011". Our first firing of new brass or factory ammunition will always be a long stretch; but after that with only a .003" bump everything should be tickety-boo.

Or, he can swap his bolt out for a 0.125" and hope that the .001" headspace is enough for reliable cycling. He could even screw his die in further if he had a 0.125" bolt.







.

Agreed. It's the die is not getting adjusted right are the press is causing a issue.