9mm primer strikes

[kimbernut]

Fired a couple hundred rounds through the Colt Pocket Nine this past weekend. (First time to the range except for a couple dozen rounds FMJ 115 gr. when I first bought it). Had four malfunctions but 3 of those were from one box(50 rds.) Win. target round NT 105 gr. JSP that I would not choose anyway for carry. The 4th failure was one out of 150 handloads.

The Win. NT factoryJSP showed a pretty well flattened primer and slight cratering around the fp strike- - - not that unusual for 9mm.

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The 150 handloads consisted of :

4.5 gr. Bullseye FC case Rainier HP 115 gr. CCI500 [email protected] OAL
The primer shows no flattening at all (still fully rounded edges).
The primer strike on the nickeled primer is mostly filled back in with shiney unplated brass leaving just a slight indentation visible.

4.2 gr.Bullseye FC case Rem GS 124 gr. WSP primer@ 1.085 OAL
The primer shows no flattening at all as above.
The primer strike is completely filled back in with shiney brass leaving no indentation visible at all.

I've never seen primer strikes like this before. Is this something I should be concerned about? Any explaination as to what is going on here would be most appreciated . Thanks.

Edit-- No pictures at present but I'll see what I can do.

 

[cordex]

Got pictures?

 

[g56]

The primer shows no flattening at all (still fully rounded edges).
The primer strike on the nickeled primer is mostly filled back in with shiney unplated brass leaving just a slight indentation visible.

Primer's can be hard to diagnose, you have partial flattening, which sounds like a high pressure warning sign to me.

I believe the best way to diagnose those primers is to load some up with a lighter powder charge and see what they look like.