RCBS Cowboy Shotshell Die 12 GA

[Sagerider]

I posted this subject on the CAS City Darksider's Den to find if others were experiencing the problem I have with the RCBS die. I received only two hits but the response showed the same results -- this die will not resize our Magtech brass shotshells after firing. I have been resizing my Magtech brass with a MEC Sizemaster to insure the fired/expanded cases will chamber without concern. The Sizemaster is not the best as it is not a full case resizing but it can resize the case mouth and base (once base down and once case mouth down).

Using the RCBS die to full length resize has been not been successful as the sizing ring has a greater inside diameter that the expanded brass exterior diameter. My fired brass measures .804 +/- and the sizing ring is .807 per RCBS. Brass at .804 will not drop into the chambers of my Fox Sterlingworth or Cimarron SXS so I am not concerned that the chambers are undersized.

 

In conversation with Customer Service at RCBS, they are willing to send a replacement ring but state the internal diameter will be .807. Not much help there.

 

For you Cowboys using an RCBS shotshell die, what are your results for resizing Magtech brass?

 

Sagerider

[Beartrap SASS#57175]

If you want a die that WILL work on those magtecs go to www.ch4d.com. They make both a full length 12ga resizing die and a roll crimp die for putting that nice rounded edge on them so they slide right in the chambers.. Ain't cheap but built like tanks and will do the job longer than our lifetimes! Have both and they're great. They're big so work best in a RCBS rock crusher and the cases NEED to be lubed.

[Garrison Joe, SASS #60708]

 

Using the RCBS die to full length resize has been not been successful as the sizing ring has a greater inside diameter that the expanded brass exterior diameter. My fired brass measures .804 +/- and the sizing ring is .807 per RCBS

 

 

 

Sounds like your chambers ARE undersized. SAAMI specs call for the diameter of the chamber right in front of the rim to be cut as 0.810 to 0.815"

 

Brass at .804 will not drop into the chambers of my Fox Sterlingworth or Cimarron SXS so I am not concerned that the chambers are undersized.

 

 

First, this sentence makes no sense the way you wrote it.

 

IF we remove the first "not" out of the sentence, it could make sense, but that would mean both the Fox and the Cimarron could still have very tight chambers, tighter than SAAMI specs.

 

This is a case where honing the chambers out to the minimum SAAMI specification (0.810") would make profound sense to me. Remembering of course, that a 12 gauge chamber should have taper to it, down to 0.798" at the crimp area (right before forcing cone).

 

Reference drawing: http://www.saami.org/PubResources/CC_Drawings/Shotshell/12-gauge%202_3-4.pdf

 

Then that RCBS die MIGHT have a chance of satisfying you (but with it using only a carbide sizing ring at the bottom of the die, it cannot put the right taper on the full-length brass shells). The ch4d die might be the only way to go to get a true full-length resize.

 

Good luck, GJ