Primer pocket web thickness

[Roninco]

Magnum, sorry to hear of your recent situation. Best of luck to you.

 

[pacowboy]

A few tenths over 20 firings is not gonna make a primer proud of the case head. And as you know, case head expansion gets to a point and almost stops, unless you keep using higher and higher pressures, but then the case head expands laterally, opening the primer pocket.
If the case head was completely inside the barrel, no expansion would take place. Alas, it isn't.
So, I should have said, until case head expansion becomes stable, as it does as it hardens with use, the web does move into the primer pocket and the pocket expands outwards.
Having trouble explaining this, lost my job today and the old brain is having trouble releasing technical info.

Cheers.

Sorry to hear you lost your job magnum. Hopefully something better comes along quickly for you.

 

[243winxb]

as it hardens with use,

Yes gets harder. Olin Brass-
Cartridge Brass-
Material is 70 copper/30 zinc with trace amounts of lead & iron , called C26000. Material starts to yield at 15,000 PSI when soft (annealed), and 63,000 PSI when hard.
Material yields, but continues to get stronger up to 47,000 PSI when soft, and 76,000 PSI
when work hardened.

 

[30BR]

FWIW, In my across the course days, Federal 308 brass would ALWAYS loosen up without even touching the pockets. That was the life limiting element for that brass. In my 30BR, squaring the pockets every time, I throw the brass out after 40 loads, just because... Pockets are still tight. Bottom line; watch what you're doing and don't get too comfortable just because you've always done it "this way"...

(I look at the primer pocket as the intake port of a race engine. Smooth is good, and sometimes bigger is worse.)

 

[RYEWSKY25284]

I measured overall length of the case then the depth of the internal portion from the mouth to the flash hole and the depth of the primer pocket itself. I subtracted those 2 numbers from the overall case length and got to my .094 web thickness. I was pulled away so I didn't have time to measure more last night. I plan to check more.

I've often wondered the answer to this question. Thanks for posting and doing the work.
It's appreciated.

 

[MagnumManiac]

Thanks guys, appreciate the sentiment.

Dunno why, but European brass seems harder than other brass, even Lapua isn't as hard as RWS, S&B or Herters.

Cheers.

 

[dartem]

I uniform primer pockets at the first loading for my autoloaders....AR, M1a, Garand to guard against the possibility of slamfires. Once only, and with a solid carbide tool (not adjustable) as tools that are adjustable tend to come out of adjustment...
Regards,
-Mike