Tikka bolt face/primer issue

[mt terry d]

Wondering if my bolt face is toast.
Having primers extrude around the firing pin. The extruded part is not the whole primer,
just around the firing pin.
The hole in the bolt face appears irregular to me but I only know enough to be dangerous.
Thoughts?
Solutions?
Thanks

 

[WeiserBucks]

Seems like the firing pin hole is oversized, any competent gunsmith can bush it for proper fitment. I've had to do a few 700s but never a Tikka.

 

[ResearchinStuff]

any chance you're overpressure?

 

[mt terry d]

any chance you're overpressure?

Yes. Working up Ackley Improved loads and just got some sticky bolt lift. However the primer piercing has been an infrequent occurrence for some time. The extrusion is recent.

 

[WeiserBucks]

Check the tip of your firing pin and see if it's deformed.

 

[mtnbound]

Yes. Working up Ackley Improved loads and just got some sticky bolt lift. However the primer piercing has been an infrequent occurrence for some time. The extrusion is recent.

Infrequent piercing for the primer does not sound like a firing pin issue. If it happened all of the time then I could see that as an issue. I would confirm your load data to make sure it’s not pressure based.

 

[Q_Sertorius]

This seems pressure-related to me.


____________________
“Keep on keepin’ on…”

 

[mt terry d]

I have a couple hundred regular 223 loads that I know are safe pressure
I’ll try shooting a bunch of them

 

[T_Widdy]

Yes. Working up Ackley Improved loads and just got some sticky bolt lift. However the primer piercing has been an infrequent occurrence for some time. The extrusion is recent.

I hade several do that while fire forming a AI also, had a couple that didn’t fire also. It’s most likely due to excessive headspace if your FF to AI. Are you seating the bullets into the lands with a reduced load to form the new shoulder?

 

[ResearchinStuff]

i've only pierced 1 primer ever, so far from an expert. but i was about 1.5 gr above where i first started primer cratering on a standard 223.

if that is your fireforming load for the AI, and you're jamming the bullets in lieu of proper headspace for the fireforming, you'll hit pressure a lot earlier than you expect without a jam.

 

[mt terry d]

No. To first FF just shooting previously loaded 223 rounds.
These are from FF brass and working to pressure.
They were causing a sticky bolt so there’s excessive pressure involved

 

[mt terry d]

Not in the lands. I cant remember for sure but I think I have a good 0.020

Okay, I just fired 8 of my known-to-be-fine 223 loads.
No issue. Picture below.
Going with the assumption I'm too hot. Think I got greedy. Saw some cratering
but no sticky bolt; until it got sticky.

Going to work back up slowly.

Question: If I load the exact same load in the Ackley Improved cases
should i expect a drop in velocity (and pressure?) from the reg 223 loads?

 

[Ringbill27]

I’m a little concerned with what going on with your ejector? I can’t say I’ve seen one dinged like that before. Both that and the primer issue make me think you are playing with some pretty high pressures.

 

[Castle Rock]

Use CCI 450 or Remington 7.5 and that won’t happen

 

[Vern400]

My thought is gas at 65,000 to 85,000 psi and maybe 2000 degrees perhaps more.... Is a plasma cutter if you've blown a few primers. You probably should check your firing pin to bore clearance. That hole is made with a drill and then probably a reamer. I doubt the machining center made it visually irregular. If your clearance is high you can get primer cratering even a normal pressures.

 

[Lawnboi]

My tikkas crater primers occasionally. I doubt you have anything wrong with your bolt if you havnt pierced primers.

What primer are you using? Cci 400 do that with anything resembling any pressure in my tikkas.