Herters Brass and CCI Primers

[KinleyWater]

All,

This morning I was doing up some work on mixed brass 44 Mag. I found that the Herters brass had primer pockets too small for CCI 300 primers. I could force them in, but it shaved the sides of the cup off and left cup material on the top of the pocket; sort of like loading cast and not belling the brass. I fired two samples - primer only, no powder or projo -and found that the primers backed out of the pocket, likely due to the loss of cup structure. The movement was sufficient to impede cylinder rotation and opening.

Bottom line - the following combination may cause you problems:

Herters 44 Rem Mag brass *EDIT* Herters brass headstamp is HRTRS.
CCI 300 primers

Suggested remedy:
Ream the primer pocket to ensure proper size.

 

[Guy Miner]

Good info.

 

[JD338]

Thank you for the heads up

JD338

 

[PJGunner]

Firing a primer case without powder and bullet will allow the primer to back out. Perfectly normal. I'll bet your brass is just fine. Look at it this way. You fire the primed case. The primer drives the case forward regardless of whether it's an empty case or a full charge round. However the fully charged case will then be driven back by pressure properly reseating the primer as if it hadn't moved. The primed case without powder and bullet cannot do this as there is no pressure delivering back thrust.
Paul B.

 

[KinleyWater]

Paul,

Good to know; thank you. The brass still physically shaved material off the primer cup during seating, so please be aware.