" small base dies, why does this term come up. Remember above I said that the chamber reamers are re-sharpened. Once they get down to a certain point they are "under spec" and the vendors use them one more time and call them "small base dies" which is a money makerNow."
I respectfully disagree. Small base sizers are made with specifically smaller dimensions than standard full length sizers. If you don't believe it, call Pacific Tool and Gauge or JGS, both in Coos Bay, Oregon.
The analogy of a hot chamber creating more pressure and case head expansion is well-known to anyone that has ever shot p. dogs. Short bursts on a machine gun would leave one round in the chamber at the end of the burst...
Also, some years ago, I had an engineer Rockwell test different brands of brass. Over the lot of the same brand of brass of the same lot number, there was a 6 percent variation in Rockwell hardness. Further more, between the brands, there was a 12 percent swing in hardness.
I don't know if PTG could provide a reamer print of a machine gun barrel, specs have to be loose to allow for carbon, dirt, etc. These dimensions would be much larger than a factory, not to mention tremendous compared to a custom Palma chamber. So, the Small Base sizer "tries" to reduce the dimension to the New Brass dimension, but brass does have a memory from the first chamber it was fired in.
I respectfully disagree. Small base sizers are made with specifically smaller dimensions than standard full length sizers. If you don't believe it, call Pacific Tool and Gauge or JGS, both in Coos Bay, Oregon.
The analogy of a hot chamber creating more pressure and case head expansion is well-known to anyone that has ever shot p. dogs. Short bursts on a machine gun would leave one round in the chamber at the end of the burst...
Also, some years ago, I had an engineer Rockwell test different brands of brass. Over the lot of the same brand of brass of the same lot number, there was a 6 percent variation in Rockwell hardness. Further more, between the brands, there was a 12 percent swing in hardness.
I don't know if PTG could provide a reamer print of a machine gun barrel, specs have to be loose to allow for carbon, dirt, etc. These dimensions would be much larger than a factory, not to mention tremendous compared to a custom Palma chamber. So, the Small Base sizer "tries" to reduce the dimension to the New Brass dimension, but brass does have a memory from the first chamber it was fired in.
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