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Primer cup hardness

Larryh128

Silver $$ Contributor
I'm looking for the absolute hardest cup primer in a large primer mag or standard. What are your experiences?
 
The CCI #34 military large rifle primers have a thicker cup in the base and a shorter anvil. Both of these modifications to the primer requires more force to set off the primer.

Below is the military drawing for the CCI #41 small rifle primer, if you look closely at the primer cup you will see its thicker in the base. These primers are the equivalent of standard CCI magnum primers to light off ball powders.

n8TOU36.jpg
 
I don't see how anyone could know.
Each primer would have to be tested for firing sensitivity (if that's what you're looking for).
This get's into strike force, area, speed, travel (momentum). Would be incredible to find & have this information, as it would be great to have striking adjustability for it.
 
I'm looking for the absolute hardest cup primer in a large primer mag or standard. What are your experiences?
I have some wolf lg rifle primers, ones with wolf picture on the box / sleeve red and black colors. Last I tried to load in 30-06 were really hard to seat.....maybe a little oversized too.
 
I have never seen any Rockwell hardness testing for primers. I doubt that there is a great difference in primer cup hardness and many primers having the same applications have the same thicknesses. It would be a reasonable to assume that any additional work hardening would occur upon forming the primer at the junction of cup bottom surface and sides.

I would guess the CCI 34 would have the least sensitivity for large rifle primers - the little anvils do not protrude much below the side ends.

Measurements:

CCI 200 side length -- .114, total length including anvil -- .128, anvil -- .014. cup thickness at end .015
CCI #34 side length -- .113, total length including anvil -- .126, anvil -- .013 cup thickness at end .015

These measurements were taken with a caliper and could be improved but the same caliper was used to measure both primers - .001 is not that much difference in CCI 34 anvil protrusion. The CCI 34's would seat deeper in equal depth primer pockets by .002 without compression and have .001 less anvil protrusion.

If primers are formed from the same sheet of brass it would seem that the sides of the cup and bottom or base would have same thickness.

As far as I know there are no major differences in primer cup thickness in large rifle primers as found in the differences between CCI 400's and CCI 450's, 41's & BR4's. I have had CCI 400's extrude into the firing pin hole in a bolt face blocking the firing pin with zippy .17 Remington loads.
 
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CCI BR4 and 450 primers have a thicker cup. They take more firing pin strike force to set them off. They are less likely to blank then any other primer. Look up primer cup thickness. There are charts on the internet. Even though the BR4 is the same thickness in large rifle, they take more firing pin hit to set them off. Matt
 

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