CCI 250 mag primers not igniting?

[elmerdeer]

Here is the problem I ran acroos today, I have 2 times fierd brass that was going on 3rd firing today, they were PFL resized.
This brass fired some loads that had pressure signs, Ex:extracter marks and slightly sticky bolt once in a while. I did back down from those loads some.
So here is what happened today I loaded some of my favourite loads and tried them with the cci 250 mag primers instead of the fed 215 primers. I did back down first and worked my way up, Now withe the origianal primer fed 215 mag they would always fire, with the cci I had 20 out of 45 rnds not go off, now I am wondering what could it be? Did I trash my brass by shooting hot loads, but my primer pockets are still pretty tight.
My action is a Stiller Predator, my caliber is 7mm Dakota, and my brass is Norma.

1) Is my brass the problem? Primer pockets are still pretty tight.
2)Are the cci 250 mag primers different in size, height, width, to make my firing pin not strike them hard enough?
3)How deep should primers be seated? I always seat primers with my rcbs hand primer and after the first squeeze I rotate the brass and squeeze again, never had a problem doing it that way before.
4)Can ther be something wrong with my firirg pin?
Thanks
Elmer

 

[Ruger007]

Did you try to fire the same one twice? i've only had a few misfires but they all went off on the second try. cci primers are known to be harder than federals.

 

[Dogleg]

I had trouble with the CCI Magnums in my .338 Edge last winter. Constant misfires lead me through the normal handload checks. Being a Savage the firing pin protrusion is adjustable, plus the free play is adjustable so that was checked as well. A 32 pound Wolff spring was swapped in without success then finally I broke into my hoard of 215Ms and the problem went away. Some of the CCI primers fired without lighting the powder. Those 90 plus grain loads of H1000 would get welded together, and discoloured to yellow. I'd have to scrape it out of the case with a probe.
The cups seem to be harder, which is why I tried so hard to make them work. It cuts down on cratering.

 

[elmerdeer]

Did you try to fire the same one twice? i've only had a few misfires but they all went off on the second try. cci primers are known to be harder than federals.

I did try firing them twice but it did not happen, how deep should primers be from the case head? Mine are .009"-.010" deep.
Thanks
Elmer