SHV wrote:What diameter is the heel of your .323" bullet?-----------bottom part .314 driving band is .323
Did you push it deeper into the case than just the heel?---------not too deep just stopped at heal line or leave a little gap
What is the diameter of the case neck with the bullet seated?----------.335
Have you slugged the bore?------not yet but I put .311 projectiles to the barrel it can be pushed totally inside with out too much effort, also I insert the 310(316) factory ammo projectile into the barrel it get in easily the rifling only scratches the wax off
thanks
It certainly sounds like the bore is around the .323" area then. Will the bullet (not the cartridge) drop all the way into the throat until it touches the rifling?
The specs call for the loaded case neck to be .327". With age, the chamber could certainly be larger than spec, but .335" is getting extreme I think.
This CIP spec also calls for the reamer to be .328" max at the case mouth and .325" in the throat. And the case length should not be over 1.130" - if it's longer it might get crimped in the throat (but you already said the empty brass chambers fine).
https://bobp.cip-bobp.org/uploads/tdcc/tab-ii/tabiical-en-page78.pdfYou said the new cases and the old factory ammo both chamber fine, what is the diameter around the neck of those cases?
You said the cast of the throat is .335", do you mean the case neck area of the chamber rather than the throat? Did you cast the whole chamber? If the chamber measures .335" it would certainly make it difficult to force a .335" case neck into it. I can only surmise that the case is being enlarged too far when seating the bullet. Which could be due to the neck wall thickness being too thick, or the heel of the bullet being too wide (it seems fine at .314"), or you need to crimp the bullet, or perhaps it's shaving lead off the bullet when seating and piling up in the case neck due to the heel. Is the bullet going in nicely without much force? Are you flaring the case mouth and crimping it back afterwards?
I would take a cast of the chamber and use those measurements to determine what I size the case neck to (probably .002" under the chamber dimension), and what size bullet (.001" or .002" under throat diameter) and heel (case neck diameter minus the neck wall thickness) I want to use. You can make a neck sizing die similar to a bullet sizing die by boring an under-size hole through a 7/8"-14tpi bolt then hone it out to the size you need (start under-size and test load and shoot before honing it out further). You can do the same with the bullet, and the heel - you would basically be doing the same as nose-sizing the bullet to fit the bore but at the other end of the bullet. To size the bullet (driving band) you push the whole bullet through a die. To size just the nose (so it fits neatly into the rifling) or the heel (to fit into the case), you push the bullet partially into a die then push it back out. You can also make a simple crimp die out of a bolt if you have to, but the bullet will also be sized down about .001" smaller diameter than the case neck by this sort of crimp die.