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I came across some 40 S&W brass, headstamp marked: "CBC". I noticed that the diameter of the flash hole is slightly wider than all my other cases. It also appears to have a primer crimp like in military cases. Anyone familiar with these, and can they be reloaded normally? Will the flash hole have an effect on pressure?
 

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I came across some 40 S&W brass, headstamp marked: "CBC". I noticed that the diameter of the flash hole is slightly wider than all my other cases. It also appears to have a primer crimp like in military cases. Anyone familiar with these, and can they be reloaded normally? Will the flash hole have an effect on pressure?
Yes

A too large flash-hole can also allow the case pressure to blow the primer cup, cause a revolver to lock-up due the setback. Factories adjust loads to fit the powder and cases, rather than junking a batch of brass. If you reload those cases, cut the load more than the starting recommended load, maybe 20-25% below the maximum or 5-10% below starting loads.

If there is a crimp, the cases are possibly military and heavier [thicker] with less internal space, that will also raise pressures.
 

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Aside from reaming out the crimp (several tools to do that) the flash hole is no problem. I used to use a chamfering tool when all I could get was CBC, and also found that repriming could be done without that step but after several angled primers I stopped and now just toss it. You can get a swaging tool and resize the pockets. There is a lot of CBC out there and it's OK brass but I now avoid it.

Start out low in the powder range and look for any signs of primer setback....

bosco

PS; I found the crimped brass a little thin in my opinion.
 
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