While a lot of this info is in another thread... I thought others might like it more cohesive.
This is gonna be about the various FP tip sizes, and styles and bolt FP holes I have found.
IMHO... All manufacturers should post FP tip sizes and bolt FP hole diameters... Yeah I know.. Good Luck.
Much like everything else in the Non- Mil-spec world of Large Frame AR's ( LFAR ) ... firing pins and bolt face FP holes can vary by quite a bit.
I am posting so someone can hopefully avoid using / purchasing a incorrect FP size.
This is not a be all list , but is some of the brands I have bought and measured.... Please NOTE, the FP style also varies... IE , Tapered v. standard.
Tapered on the left.. standard on the right.. the middle is in the pic because of the less than squared of edges at the rings.
I will say , and to cut to the chase... try to buy a brand bolt that comes with a firing pin.
Using a wrong size FP tip size , in a poorly matched bolt FP hole diameter will cause excessive primer cratering and primer flow.
Measurements were done with a Pin gauge set and caliber.
For the "most" part, "standard" 308 BCG's and bolts ( Non HP ) come with a approximate FP tip size of .076-.079 and bolt FP hole of .080-.083
My List of measured "308" FP tips and Bolt Hole sizes...
3ea Generic CDNN bought 308 FP.... .078"
PSA / Toolcraft 308 BCG... FP tip size.. .077" , bolt FP hole... .081
10ea PSA FP measured.. varied between .076" ( 2ea ) .077" ( 7ea )and .079" ( 1ea )
Standard style. ( Non Tapered )
Please NOTE.. the PSA dual ejector 6.5CM BCG uses a smaller HP FP tip size . More later
Links provided to be specific.
https://palmettostatearmory.com/psa-pa10-308-nitride-bolt-carrier-group-516446490.html
https://palmettostatearmory.com/psa-pa10-308-nickel-boron-bolt-carrier-group.html
https://palmettostatearmory.com/308-firing-pin.html
Lantac 308 FP , Nib 308 Bolt, and Nitrated 308 bolt, .... .076" FP tip size ( 4ea ) .081" Bolt FP hole on both... these are sold as "spare parts".
Standard style. ( Non Tapered )
PLEASE note... the Lantac ENHANCED BCG uses a different FP tip size and Bolt face FP hole !! ( More later )
https://www.lantac-usa.com/product-page/lantac-308-7-62-bolt-choose-finish-nib-qpq
https://www.lantac-usa.com/product-page/lantac-308-7-62-firing-pinFP
RTB Blem 308 BCG ( Toolcraft ? ) ... .076" FP tip size,... .080" bolt face FP hole.
Non tapered FP.
Link no longer available
Others measured info...
Fulton Armory actually shows a 308 Bolt for DPMS pattern.. for use with a .078" FP
https://www.fulton-armory.com/bolttitanstripped.aspx
https://www.fulton-armory.com/bolttitanstripped-2.aspx
https://www.fulton-armory.com/firingpinchrometitan.aspx
msgriff... "The original DPMS LR-308 bolts were a 0.080" bolt face firing pin orifice with a 0.076" firing pin tip diameter."
Non tapered.
Top O' Texas tapered v. standard profile FP photo.. Some of the tip sizes vary on the Tapered FP and Standard profile.
This is gonna be about the various FP tip sizes, and styles and bolt FP holes I have found.
IMHO... All manufacturers should post FP tip sizes and bolt FP hole diameters... Yeah I know.. Good Luck.
Much like everything else in the Non- Mil-spec world of Large Frame AR's ( LFAR ) ... firing pins and bolt face FP holes can vary by quite a bit.
I am posting so someone can hopefully avoid using / purchasing a incorrect FP size.
This is not a be all list , but is some of the brands I have bought and measured.... Please NOTE, the FP style also varies... IE , Tapered v. standard.
Tapered on the left.. standard on the right.. the middle is in the pic because of the less than squared of edges at the rings.
![IMG_1041-638186.jpg](https://www.ar15.com/media/mediaFiles/171545/IMG_1041-638186.jpg)
I will say , and to cut to the chase... try to buy a brand bolt that comes with a firing pin.
Using a wrong size FP tip size , in a poorly matched bolt FP hole diameter will cause excessive primer cratering and primer flow.
Measurements were done with a Pin gauge set and caliber.
For the "most" part, "standard" 308 BCG's and bolts ( Non HP ) come with a approximate FP tip size of .076-.079 and bolt FP hole of .080-.083
My List of measured "308" FP tips and Bolt Hole sizes...
3ea Generic CDNN bought 308 FP.... .078"
PSA / Toolcraft 308 BCG... FP tip size.. .077" , bolt FP hole... .081
10ea PSA FP measured.. varied between .076" ( 2ea ) .077" ( 7ea )and .079" ( 1ea )
Standard style. ( Non Tapered )
Please NOTE.. the PSA dual ejector 6.5CM BCG uses a smaller HP FP tip size . More later
Links provided to be specific.
https://palmettostatearmory.com/psa-pa10-308-nitride-bolt-carrier-group-516446490.html
https://palmettostatearmory.com/psa-pa10-308-nickel-boron-bolt-carrier-group.html
https://palmettostatearmory.com/308-firing-pin.html
Lantac 308 FP , Nib 308 Bolt, and Nitrated 308 bolt, .... .076" FP tip size ( 4ea ) .081" Bolt FP hole on both... these are sold as "spare parts".
Standard style. ( Non Tapered )
PLEASE note... the Lantac ENHANCED BCG uses a different FP tip size and Bolt face FP hole !! ( More later )
https://www.lantac-usa.com/product-page/lantac-308-7-62-bolt-choose-finish-nib-qpq
https://www.lantac-usa.com/product-page/lantac-308-7-62-firing-pinFP
RTB Blem 308 BCG ( Toolcraft ? ) ... .076" FP tip size,... .080" bolt face FP hole.
Non tapered FP.
Link no longer available
Others measured info...
Fulton Armory actually shows a 308 Bolt for DPMS pattern.. for use with a .078" FP
https://www.fulton-armory.com/bolttitanstripped.aspx
https://www.fulton-armory.com/bolttitanstripped-2.aspx
https://www.fulton-armory.com/firingpinchrometitan.aspx
msgriff... "The original DPMS LR-308 bolts were a 0.080" bolt face firing pin orifice with a 0.076" firing pin tip diameter."
Non tapered.
Top O' Texas tapered v. standard profile FP photo.. Some of the tip sizes vary on the Tapered FP and Standard profile.
![IMG_20231203_130006-3242555.jpg](https://www.ar15.com/media/mediaFiles/171545/IMG_20231203_130006-3242555.jpg)
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