Would that also apply to dies making bullets and cases?Our 7/8-14 reloading dies are solely located in the reloading press by the the threads on the die and the threads in the press. It is difficult to measure the runout of the die threads to the axis of the die, or to measure the runout of the press threads to the top surface of the press. So the die and press manufacturers rely on best machining practices to keep tolerances within reasonable limits, but there will be some misalignment due to the necessary clearance between the external threads of the die and the internal threads in the press. Will an o-ring help? Maybe, maybe not.
I'd expect that commercial dies do not rely on just the threads for alignment, they probably use a pilot diameter that can be held in close alignment to the axis of die and/or a shoulder that can be held perpendicular to the die axis. The best approach would be to not use threaded dies, but to use a clamping arrangement to hold the die in the press.
Would that also apply to dies making bullets and cases?
Sierra, Starline, Hornady and Lake City Arsenal give tours of their facilities.I'd guess that commercial bullet and cartridge equipment is much different than our typical reloading dies. Probably they would have dedicated multi-station die plates for each cartridge, with the cartridge or bullet form machined precisely in the plate. I need to find a company giving tours of their manufacturing facility.
Check-6 right here on TFL:I need to find a company giving tours of their manufacturing facility.
For what it's worth, certainly agree with that concept. None of my accuracy loads use an expander ball, have more interference fit than most find acceptable and use Redding comp seater if available. However was responding to another post about self centering the expander ball.For what it's worth, best accuracy happens when the expander ball is removed and the full length sizing die neck is honed out to about .002" less than a loaded round's neck diameter. The die is set in the press to set the shoulder back a couple thousandths.
Sierra Bullets pioneered this in the 1960's.