Sendero Firing pin, cross pin failure

[Bnhpr]

A friends sendero blew the firing pin out the back of the bolt today, and it gave him a minor cut on his hand. The ejected shell had a hole in the firing pin. The load was a hand load 2 grains under max, with 165 Hornady SST's.

Is this an unusual failure, or common for an over pressure?

 

[Kampfeld]

I don't see how this is possible, the firing pin spring would keep the pin from coming out the back.

 

[Don]

I don't see how this is possible, the firing pin spring would keep the pin from coming out the back.

He probably means firing pin assembly= firing pin, spring, shoe, and shroud.........with the shroud threads stripping out of the bolt body, especially the aluminum variety..............Don

 

[warthog]

He probably means firing pin assembly= firing pin, spring, shoe, and shroud.........with the shroud threads stripping out of the bolt body, especially the aluminum variety..............Don

I have loaded lots of over pressure loads,some blown primers,some,with no primers left,some that the head of the case was stuck in bolt face,even had firing pin slamed back into bolt so hard that it even broke trigger sear because of blown primer. After much brass frag. I just got older and quit while still alive. Don't no what your brass looks like,recheck load,check neck clearance,length of brass crushed brass to long in neck. All will kill you. (Grace Under Pressure)

 

[Dans40X]

F/Pin Striker Cross Pin

If-If the f/pin striker cross pin(.093"x.435") failed,the striker would be the only un-captive part that could possibly fall out of the bolt assy.
The F/pin,spring,shroud would still be captive in the bolt assy by the threads on the shroud.

If-If the threads of an aluminum F/pin shroud stripped off completely the F/pin,spring,shroud & striker would still be a captive assy-by the F/pin cross pin.

Of the thousands of Rem F/pins that I've timed/built up over the years,I haven't experienced the above mentioned problem - ever.

 

[Bnhpr]

Ok, I've attached a pic. I have not seen the assembly, but Nathan said he screwed it out, by hand, at the range. The threads are not stripped, but the firing pin was hanging out, like in the picture.

He is going to take the rifle down to a gunsmith in Goliad, TX, where he lives to have it looked at.

The other 4 cases in a series of 5 supposed to be- identical loads, looked ok, with a little flattening, but not bad.

The powder was IMR 7828 loaded in a 300 mag.

 

[Dave Short]

How did it get past the trigger? What is the spring doing at this point? Is the firing pin stuck in the shroud? Was the cocking piece separted(you mentioned the cross pin)?........................I'd like to see more pictures.............this isn't making sense.............

-Dave-

 

[RJM]

Could he have gotten a pistol primer mixed in with his rifle primers? It looks like a pieced primer vented a bunch of gas into the bolt!
Regards, Ron

 

[Bnhpr]

How did it get past the trigger? What is the spring doing at this point? Is the firing pin stuck in the shroud? Was the cocking piece separted(you mentioned the cross pin)?........................I'd like to see more pictures.............this isn't making sense.............

-Dave-

The rifle is 1000 miles from me right now, and I'm going on what is reported by a firend and owner of the rifle.

He has taken it to a gunsmith, and there will be a full report within a few days.

It is very possible that primers were mixed up. There was a 2 1/2 year old that attacked the loading bench a few weeks ago, she's known to do things like break the primer feed tube off the press, for entertainment purposes. I bet that is what happened.

Ben