Help needed in ordering a chamber reamer

[alinwa]

I'm wondering how much more the chamber at those dimensions should be than the brass to ensure smooth chambering without excessive expanding on firing.

Please explain what this means?

 

[South_Pender]

Please explain what this means?

Here's what I meant: If you have an unfired case you plan to use that is, for example, .430" in diameter at the shoulder, how much greater than that should the chamber dimension be at that point to be sure of smooth chambering and sufficient room to expand? Similarly, if the diameter of the unfired case you're planning to use mic's .4372 at a point .20" up from the base, what should the chamber diameter be at that point? .439"? .440"?

Hope it's clear now....

 

[mturner]

Here's what I meant: If you have an unfired case you plan to use that is, for example, .430" in diameter at the shoulder, how much greater than that should the chamber dimension be at that point to be sure of smooth chambering and sufficient room to expand? Similarly, if the diameter of the unfired case you're planning to use mic's .4372 at a point .20" up from the base, what should the chamber diameter be at that point? .439"? .440"?

Hope it's clear now....

The dimension at .200" should be between .4395" and .440". If you get it to tight, expect a click on extraction. Also make the inside neck shoulder junction with a .060" radius, not a .075" radius. Keep headspace a 1.075" from boltface to shoulder, just like you already have it.

Michael

 

[South_Pender]

Thanks to all of you for your insights and advice.

I've gone ahead and ordered the reamer from Dave Manson.