The PRC die "problem"

Alex Wheeler

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There are a number of people experiencing sizing issues with the PRC case. When designing a chamber, brass, and resize die there is no one size fits all. We want good hard case brass, but its harder to size. We dont want sloppy chambers either. I have experience with designing reamers with hard brass and in my opinion the PRC base diameter is just too small to work. The die specs are not the main problem. You cant make a die much smaller than the solid web without it cracking. And once a case head expands a little no die can fix the clickers that you will get.

Looking at the 300 PRC and ADG brass there is only .003-.0035" difference between a virgin case head and the chamber. Thats not enough for this type of brass in a magnum case head. And will lead to long term problems.

I already have reamers spec'd out for myself with other changes, but I have spec'd new ones and will post the prints here with the only change being to the base size. That in my opinion should have been the Saami spec to begin with. They should solve most all of your sizing issues. The dies still needs to measure .5295"-.530" at the base though. Many are polished out.
 
There are a number of people experiencing sizing issues with the PRC case. When designing a chamber, brass, and resize die there is no one size fits all. We want good hard case brass, but its harder to size. We dont want sloppy chambers either. I have experience with designing reamers with hard brass and in my opinion the PRC base diameter is just too small to work. The die specs are not the main problem. You cant make a die much smaller than the solid web without it cracking. And once a case head expands a little no die can fix the clickers that you will get.

Looking at the 300 PRC and ADG brass there is only .003-.0035" difference between a virgin case head and the chamber. Thats not enough for this type of brass in a magnum case head. And will lead to long term problems.

I already have reamers spec'd out for myself with other changes, but I have spec'd new ones and will post the prints here with the only change being to the base size. That in my opinion should have been the Saami spec to begin with. They should solve most all of your sizing issues. The dies still needs to measure .5295"-.530" at the base though. Many are polished out.
Thanks Alex.....I had my barreled action made up at WTO, how can I have or do this change to an existing chamber? It was their "match"chamber and I don't know the specs of it.
 
Alex is correct about a fine line between sizing or not! Thats why custom is better than SAAMI if you do it right. We are using the same brass for the 30 SM and have had no problems because Ben listens and I get what I pay for!!
.0005" can make all the difference!
You using Hornady resizing dies for your 30 SM?
 
There are a number of people experiencing sizing issues with the PRC case. When designing a chamber, brass, and resize die there is no one size fits all. We want good hard case brass, but its harder to size. We dont want sloppy chambers either. I have experience with designing reamers with hard brass and in my opinion the PRC base diameter is just too small to work. The die specs are not the main problem. You cant make a die much smaller than the solid web without it cracking. And once a case head expands a little no die can fix the clickers that you will get.

Looking at the 300 PRC and ADG brass there is only .003-.0035" difference between a virgin case head and the chamber. Thats not enough for this type of brass in a magnum case head. And will lead to long term problems.

I already have reamers spec'd out for myself with other changes, but I have spec'd new ones and will post the prints here with the only change being to the base size. That in my opinion should have been the Saami spec to begin with. They should solve most all of your sizing issues. The dies still needs to measure .5295"-.530" at the base though. Many are polished out.


I have a custom Hornady .528 die and it does not fix the issue for the reasons you mentioned. The SAAMI chambers are too small. The 300 has the same issue but I don't see as many discussing it.
 
I'm having problems with resizing two 6.5 PRC's. Bought a second set of dies but no help.....
If you've got two sets of resizing dies, here's a poor man's solution... Required a side grinder with a metal cutting blade and submerging the die under water while cutting off the top and some of the bottom off a spare full length resizing die... If you own or have access to a lathe, even better.

Whidden made me three resizing dies for my 338 Lapua Rogue. Tried they're darndest, yet none of them were small enough in ID to sufficiently resize near the case head. I cried uncle and modified one of the spare resizing dies to resize my cases near the case head. It's a very special "customized", custom Whidden resizing die. :) Look's like I found it in a dumpster, but it works superbly. It's very adjustable. I adjust it down on the case during resizing just enough for easy chambering.

Look's like I should apply for a patent.

Whidden Resizing Die Pic.jpg
 
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