not sure about this one

[vapochilled]

9mm 124 grn JHP(precision delta)
5.3 grn power pistol, way below max load
COL 1.075", plenty of margin there
Chrony has em at 980fps, primers are telling me I'm wayyyy over pressure!
No case bulging, just flat primers and smeared firing pin indent.
Ideas gang?
I'm going to play with COL, but power pistol seems to be a mid rate burn, so I'm not sure I'll solve this with COL.
Someone else suggested a problem with the breech/pin ?
Primers were a mix of federal AND CCI! mixed brass.

Maybe it's a non issue, I'll post a pic or two when I can of the primers

[Jason In Erie]

what pistol are you using? Some are notorious for making a swipe on the primer.

[M&P Chris]

I would adjust your OAL. I load 9mm to 1.125".

[dk99358]

I'd really limit my cases to ONE manufacturer and ONE brand of primers while trying to sort it out, the fewer the variables, the better.

Dale

[vapochilled]

I'd really limit my cases to ONE manufacturer and ONE brand of primers while trying to sort it out, the fewer the variables, the better.

Dale

Not a bad idea!
M&P, someone else suggested that also
It's a P226 btw

[Rik Bitter]

My son's favorite 9mm target load is pretty close to yours.

125 gr LRN
Mixed range pickup brass
5.2 gr. Power Pistol
CCI Small Pistol Primer
1.118 OAL

No issues that I know of as far as flat primers from overpressure. The only real difference looks like the OAL. Back off on the seater die a bit and see if the problem goes away.