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Yeah exactly about the donut, it crushes into the front of the chamber. This was a virgin chamber and was built with the correct amount of shoulder crush, but the false shoulder at the front of the chamber makes a tighter fit in front of the shoulder and holds the case back against the bolt face more squarely than crushing along a datum line on the shoulder IMO. Very consistent and repeatable results, very good fireforming loads, good case life.
I forgot about the datum line being what touched in the chamber on a crush fit standard cartridge to AI conversion. For whatever reason I was thinking it was the neck shoulder junction.
Yup.
I said "a datum line", not in reference to the headspace comparator datum line size but in reference to an AI crushes at a point on the shoulder of the case based on the diameter of the chamber neck and where along the shoulder that full neck diameter of the chamber is reached, since the the neck has to have radial clearance for expansion. The false shoulder crush is fully in the neck of the chamber, not on the shoulder at all. I can chamber a false shoulder round and see where the neck/shoulder junction is in the chamber based on how much of the false shoulder gets jammed in. It's a visible bright ring around the false shoulder if you remove a case before firing.
This is what I thought but I understand what quietTexan is saying and what you both mean. I'm picking up what you are putting down. The "fulcrum" is in the same place just the "lever handle" is a different shape when comparing the two styles of fire forming.
A picture speaks a thousand words!!! This is what I thought it would look like. Obviously it would be that case in an 243AI case gauge so more gap in the shoulder and a little in the body.
DJ's Brass service in Alabama. You can find it on the net. Considerating the cost of components, and barrel wear, IMHO, his service is cost effective.
My 22-250 AI method is to simply load the standard case with a standard 22-250 powder charge and have the bullet jammed into the rifling. This has worked well for me and provides a fully formed case and is certainly accurate enough to hunt with.
In all the Ackley calibers I've ever owned (a lot)
I use Unique or Herco, 10 grains for 308 size cases, 12 grains for 30-06 and larger, Put over top of powder some cornmeal, malto-meal, cream of wheat or what ever you have on hand. Light a large candle and let it burn away from your loading area. When there is a large amount of melted wax, Pour it into a jar lid about 1/4" thick, When cooled push your loaded case neck into it by holding the lid upside down, This will effectively seal the powder and cornmeal into place. I have experimented with different amounts of powder, You will never get sharp corners of the shoulder, Neck junction or case Shoulder junction unless you actually use cases loaded with the proper amount of rifle powder and a seated bullet that is jammed into the lands. But many of the rounds I am using are barrel burners, SO I prefer not to send bullets down the barrel, And the way things are now, They are hard to get and expensive.
