Diagnosing lightstriking 9mm in G17 and MP9

[nza]

I'm reloading 124 JHP (as supplied by CURESE) in nickel brass.
All of my reloads are lightstriking with the G17 and with the M&P 9mm
But are totally fine with my NP29 1911. All factory loads of any kind feed find. I suppose I could take a factory round and emulate its properties, but wnated your feedback.

I have no FTFs, and they feed fine into both of the plastic guns, just lightstriking with no ignition. I suspect the round is seated too far into the chambers of both guns, causing the strikers not to reach the primer.

I have:

• OAL 1.130"
• Bullet Diameter 0.354~0.355"
• Case Length 0.745"
• Width at Case mouth 0.378"
• Width at Case base 0.388"

I am using CCI Primers, with 4.8gn of Unique.
on a Lee Turret setup with carbide dies
Any help would be appreciated

 

[Wendell]

I suspect some of your primers are not fully seated - causing the strikers to sometimes seat the un-seated primer and not have enough reserve energy to fire the primer.

 

[Cerdan]

I agree with Wendell. Could be your NP29's firing pin strikes with greater force, managing to ignite the high primers when the other two can't.

With regards to your theory, how would you explain a cartridge that headspaces on the mouth chambering too deep?

PS I started reloading on a Lee turret press; the first problem I ever encountered with my loads was high primers...

 

[Wendell]

With regards to your theory, how would you explain a cartridge that headspaces on the mouth chambering too deep?

I think you'll find that it actually headspaces on the extractor.

Charles Petty wrote about this years ago. I remembered his article last year after I fired a 9x19 that someone redface had loaded into a .40 magazine. Yup.


It does headspace on the extractor.

 

[nza]

Just wanted to update, that I finally had the chance to test out the rounds. I gave the lee press handle a little more pressure, and seated in the primers. They all fired off no problem in all the guns. Thanks.
I recently upgraded the lee turret press, and i guess the primer seater still needs some breaking in....

 

[sevoman]

CCI primers are notoriously "hard".I had a few misfires in my Glock 17(although I do also have a ligthened striker spring which would contribute to this).I have zero problems with federal or Winchester primers though.