Firing Pin - Confirmation needed Please

[WSAR15]

Am I correct in saying that the firing Pin in a Type II bolt is the same as in the AR15?
Thanks

[grayfox]

Most of the time, is what I would say. If this particular bolt is a 0.136 face depth, and is longer than the std 556 bolt by 0.011, then it can use the standard 556/223 firing pin. I think I've seen or heard of some 0.136 depth faces having bolt length equal to the 556 (? could be wrong on this, but just in case)... so in that case the pin with that bolt is probably 0.11 shorter than the standard 556/223 pin.
So, measure the bolt's length. A true grendel bolt has the extra length tacked on to the rear to compensate for the 0.136 depth face (which is a 0.11 nominal deeper than the 223).
Hope this makes sense.

[grayfox]

did some checking with the custom google 65grendel search engine, and from a thread in 2018 Vascar2 wrote the following, in that some bolts were made at 2.800, which is not the spec Grendel bolt length...
Grendel bolts should be 2.810 (+/- tol) so a standard firing pin at 3.280 +/- some 0.001 or so tolerance would work...
Vascar2, 8/14/2018:
"I hate to bring this up again as it has come up before but when Alexander Arms introduced the 6.5 Grendel bolt AA used a .136 bolt face depth. AA added .01 length to a standard AR-15 bolt which is 2.800 length so a AA 6.5 Grendel bolt should measure 2.810 from the outer most face to the rear of the bolt. AA used the 2.810 bolt length so a standard AR-15 firing pin can be used with an AA 6.5 Grendel .136 bolt.


There have been reports of pierced primers from excessive firing pin protrusion with 6.5 Grendel .136 bolts that are 2.800 length like Toolcraft. A milspec firing pin is 3.280 + or - .001 and will work as designed with a 2.810 AA 6.5 Grendel bolt. Using a milspec length firing pin in a 2.800 length Toolcraft .136 6.5 Grendel bolt may produce pierced primers. You can get an extra .01 firing pin protrusion from the shorter 2.80 bolt. Throw in the variation in manufacturing tolerance and you might experience pierced primers. Some manufacturers were supplying non milspec (shorter) firing pins with the 2.800 6.5 Grendel bolts.


Just something to be aware of if your .136 bolt face depth 6.5 Grendel bolt measures 2.800 overall length, probably should have shorter firing pin. A person can shorten a milspec firing pin by .01 [Note: use a SS pin, not chromed or nitrided!!] to account for a shorter bolt length." (end quote)

[A5BLASTER]

did some checking with the custom google 65grendel search engine, and from a thread in 2018 Vascar2 wrote the following, in that some bolts were made at 2.800, which is not the spec Grendel bolt length...
Grendel bolts should be 2.810 (+/- tol) so a standard firing pin at 3.280 +/- some 0.001 or so tolerance would work...
Vascar2, 8/14/2018:
"I hate to bring this up again as it has come up before but when Alexander Arms introduced the 6.5 Grendel bolt AA used a .136 bolt face depth. AA added .01 length to a standard AR-15 bolt which is 2.800 length so a AA 6.5 Grendel bolt should measure 2.810 from the outer most face to the rear of the bolt. AA used the 2.810 bolt length so a standard AR-15 firing pin can be used with an AA 6.5 Grendel .136 bolt.


There have been reports of pierced primers from excessive firing pin protrusion with 6.5 Grendel .136 bolts that are 2.800 length like Toolcraft. A milspec firing pin is 3.280 + or - .001 and will work as designed with a 2.810 AA 6.5 Grendel bolt. Using a milspec length firing pin in a 2.800 length Toolcraft .136 6.5 Grendel bolt may produce pierced primers. You can get an extra .01 firing pin protrusion from the shorter 2.80 bolt. Throw in the variation in manufacturing tolerance and you might experience pierced primers. Some manufacturers were supplying non milspec (shorter) firing pins with the 2.800 6.5 Grendel bolts.


Just something to be aware of if your .136 bolt face depth 6.5 Grendel bolt measures 2.800 overall length, probably should have shorter firing pin. A person can shorten a milspec firing pin by .01 [Note: use a SS pin, not chromed or nitrided!!] to account for a shorter bolt length." (end quote)

This right here is why I buy stripped bcg's and add my own parts too it.

Never an issue going that route.

I get my bcg from righttobeararms and my bcg parts off joebobs and my bolts from here on the group buy.

Has worked properly ever single time.

[VASCAR2]

Current production Toolcraft 6.5 Grendel bolts are reported to be 2.810” but still a good idea to measure the bolt length.