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Discussion Starter · #1 ·
A few things to note about that drawing, first in the center bottom box it says "tolerances' +-.001". If PTG grinds that reamer to the minimum making the base at the chamber .421" Hornady 120gr SST ammo will stick in the chamber. The necks will be .307" and the freebore will be .2771" All of those dimensions can cause issues with certain ammo.

ETA- In addition the size dies are tied into those problems. Big long argument years ago. Small base dies resize the brass .002" smaller in diameter than FL size dies that is all, the user is responsible to adjust the dies up and down for the shoulder set back. I called every die manufacturer and asked what their design diameters were. Redding would not answer. Hornady said all of their dies size the brass .004" under the minimum chamber diameter size making them small base dies. RCBS and Forster said their FL dies size the brass on all cartridges .002" under minimum chamber size and their SB dies size the brass .004" under the minimum chamber size. Taking into consideration size dies also have tolerances.
So some of the old timers here will remember the arguments between EWP and I, we went round and round about this. IF PTG grinds a reamer to the minimum size and people use FL dies that are made to their maximum diameter brass can stick in the chamber. I had that issue with the Redding dies. Tim W found a set that would push the shoulder back .020" shorter than SAAMI spec if the dies were screwed down to the shell holder as the instructions said. If people followed the instructions they would have blown primers since nothing was behind them holding them in the case.
If you haven't heard this before DON"T JUST SCREW THE DIES DOWN TO THE SHELL HOLDER.
 

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H, I added that second paragraph to the same post content in the "history" thread.
 
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Thanks again. I think that it is useful that your information gets put in a "sticky" because new shooters are finding this cartridge every day and it is difficult to wade through over a decade of posts to find it.

Another problem with the PTG drawings is that there is no "revision" information to let you know what changes were made and when. There are at least three different versions of that drawing, each with different dimensions but all share the same date of 1/8/2004.
 

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Discussion Starter · #4 ·
Thanks again. I think that it is useful that your information gets put in a "sticky" because new shooters are finding this cartridge every day and it is difficult to wade through over a decade of posts to find it.

Another problem with the PTG drawings is that there is no "revision" information to let you know what changes were made and when. There are at least three different versions of that drawing, each with different dimensions but all share the same date of 1/8/2004.
Oh yeah they also all have the same print #.
 
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