Primer pocket depths?

[Deleted member 107666]

Edit...I think I found my answer. .127-.132 is the min/max depth.

Is there a standard folks aim for to uniform depths too? getting about .130-.131...the virgin brass as it came seems to measure from .128 to .1275

Amazingly google or the search function here didnt give me any results.

Uniform is uniform, but is an exact depth range the goal? .131 good?

 

[MagnumManiac]

Many disagree with my method and theory.
Factory pockets are concave, which directs the flash into the centre of the pocket and through the flash hole like a funnel. I DO NOT change this in ANY way.
I use the depth of the primer BELOW the case head as my guide.
I then use a set distance rod to give me that depth.

A primer is designed to work perfectly and consistently ONLY when the anvil legs and primer cup are flush with each other when touching the bottom of the pocket, any other condition, high or over stressed, changes ignition between shots.
I prefer to uniform pocket diameters without changing depth, as there is enough leeway in primer cup depth to allow a flush or just below flush condition when both the anvil and cup are touching the outer edge of the pocket.

This is my way, and I can get .1's in my comp guns WITHOUT messing too much with primer pockets.
I will also add that small rifle primers are more consistent in regard to ignition over large rifle primers. The pressure trace says so between the 2 in my 6.5x47 every time I test side by side. Have run the same test side by side with my 22-250AI using the same SR & LR primed brass, and the SR is far more consistent on start pressure.

Anyway, I'm sure others will poo poo my theory.

Cheers.

 

[Mikecr]

I set 2thou primer crush with an indicated K&M seater. Of course I need this to put primers slightly below flush of case heads.
So I'm checking pocket depths to standard & shaving if needed. Often this is no more than squaring up of pockets near the edges.
That is, with Lapua & Norma brass.
Sinclair uniforming: https://www.sinclairintl.com/reload...m-primer-pocket-uniformer-kit-prod104707.aspx

 

[MagnumManiac]

If you speak to techs making primers, they always say that a primer works BEST at .005"-.008" below flush with between .002"-.003" crush.
This crush pre-loads the primer pellet, making ignition easier.

I too, use .002" crush on my primers by measuring them before and after seating.

Cheers.