.45-70 OAL Question

[MEHavey]

Before you do that !!!
Start (just start) a loaded round through your sizer (minus the primer stem)
and see if that doesn't "iron-out" any near-mouth bulges

 

[GJeffB]

Unnecessary. The sizer and expander made them perfect.
Good thought, thanks

-jb

 

[GJeffB]

Sorry, it's generally bad form to reply to one's own post. But in this case ...
Yep, the crimp was the problem. All the lightly flared/crimped 405grs chambered, locked, and fired without issue.
And after deconstructing and rebuilding the 300grs rounds, all have chambered and lock, looking forward to sending them with confidence.

-jb, finishing this up

 

[Charlie98]

finishing this up

Didn't happen without a follow up after your shooting!

 

[GJeffB]

"All the lightly flared/crimped 405grs chambered, locked, and fired without issue."
This was a function fire test only, and it passes the test. No failures of any kind. That's good enough for me at this point, granted a pretty low bar Ongoing will be "normal" load development and accuracy testing.

-jb, following the OAL thing elsewhere