primer pocket depth

[Murray Brook]

@Webster
Thanks for the post, but there does come a point where depth matters. I once had Hornady 308 Match cases with the pocket deep enough that the cartridges would not go off. Problem right now is I don't have the rifle yet to test. Most of the research I've done says that primers should be .003-.006 below flush. Mine are more than double that on most cases.

 

[Webster]

@Webster
Thanks for the post, but there does come a point where depth matters. I once had Hornady 308 Match cases with the pocket deep enough that the cartridges would not go off. Problem right now is I don't have the rifle yet to test. Most of the research I've done says that primers should be .003-.006 below flush. Mine are more than double that on most cases.

The firing pin protrudes about 0.055 - 0.065" from the bolt face. The firing pin can always reach the primer with force. There is no such thing as a proper primer depth below the case head. They are supposed to touch the bottom of the pocket. If they are not seated to the bottom of the pocket some of the firing pin energy is lost pushing the primer deeper into the pocket. The 2-3 thou number exist only so closing the bolt doesn't push the primer in deeper. For semi auto guns you could get a slam fire if the primer protrudes.

 

[Murray Brook]

@Webster
Thanks for the info.Maybe I'll be able to use these cases after all. I have no problem seating them to the bottom of the pocket.

 

[oldduc]

I unintentionally have a new primer pocket test in progress. Today I did 50 pieces of new Norma 6 Dasher brass with my RCBS primer pocket uniformer. After uniforming, I started to seat some Fed 205M primers and noticed they were pretty deep in the pocket. I measured the fresh cut pockets and found they are 0.135 deep, about .011 deeper than new. The faces of seated primers are about 0.020 below the cartridge base. WTF? The depth of the cutter is adjustable, but I have done at least a thousand cases with it and never touched the adjustment. It somehow loosened up. Apparently it is time for a new one.
Since this is about $50 worth of brass, I decided to see if it is still usable. I used one of the cases I had primed and fired it in the rifle. It fired ok and the firing pin indent looks normal. I plan to go ahead and load some of the cases and shoot them to see if they will maintain a gas seal, as one of the posters above questioned.

 

[243winxb]

Keep an eye on the bolt face for pock marks. Let us know what happens.

My small uniformer doesnt have an adjustment. Its fixed. I think it Redding carbide? Without going out to look.