Primer pockets

joe16

joe16

Hammer Time Executive member
This past year there has been a lot of posting about primer pockets and pressure (this place is awesome). So I wanted to share a new procedure that I added to my bench. I contacted BFD today to see where he thought this would be best added and after chasing down his thread (there was a lot of derail at the end) and I decided that I didn't think people would read all the way to the end. He also suggested that I start a new thread and he and GL would do a Sticky. 🤷

I'm not sure if any one person has the right procedure sitting at their bench without the correct pressure gauges and barrels to come up with the correct answer, I'm pretty sure I don't! But what did I learn this year from all these discussions? I learned about pin gauges. So I decided to add a pin gauge to my procedure, each time I fire piece of brass I will Decap it and measure the hole with a .2100 pin gauge if it fails it goes in the trash. This is a mechanical test that I can wrap my brain around and not have to use the calculator or the dial calipers or any of the other means of guessment.

Depending on manufacturer and where ordered from, it was basically $10 to the house,. Having OCD like most hand loaders, I don't mind one more stroke on the handle😳 watch your jokes people🤣. I'm also quite sure that there's a few of you that already do this. I just wished I would have learned it years ago, that's all. I just wanted to share this with y'all.

Joe
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I recently bough go no-go pin gauges off Midwayusa, iirc 12 bucks each ( large and small primer pockets)
I think it was from a thread discussion here somewhere.

They also check pocket depth.
 
Berrnard said:
where did you get your pin?

is .21 for large or small pockets?
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A friend of mine ordered them out of his McMaster Carr catalog. The one that I have is made by Meyer Gage.

Sounds like ordering the ones from Midway would be the way to go.
 
Not that I dont trust the brand sold at Midway, but McMaster pin gauges come with a certificate of accuracy. A good set of gauge pins will be the most accurate way to measure hole size.
 
@joe16 I am ecstatic! :p :cool: Especially after being affectionately named "Mr. Pressure" by @Farleg!
Seriously, that pin gauge is a dandy way to have a go/no-go gauge! I bought a Harbor Freight "Numbered" drill bit kit for opening gas port holes in ARs. I looked at the smooth ends of the drill bits one day and mic'd them with my Mititoyo micrometer and calipers. I found the calipers were accurate enough and thus I had my poor man's pin gauge set!

Most primers are .2105 and most virgin brass pockets are .208 "ish". So that virgin pocket has some crush upon the primer being inserted. (Naturally...) So, you tossing the brass at .210 is a good place. I know @ .211 and it's a guarantee I'm loosing a primer. I once found live primers in the bottom of my ammo box. The pockets were .2115-.212. The bolt face got seared for a while before I figured out the whole primer pocket thing.
 
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Brownells sells go/no go gauges for primer pockets. Lg Rif/lg Pistol and Small /Rif, Sml/pistol.
They also indicate primer pocket depth. Easy-peasy one step check before you waste a primer on a ruined piece of brass.
I can take a photo if anyone is interested and post it.
 
I know I excel at ignorance and lazy. Therefore, I have no idea what one uses the gauge for. So you check the size of a primer pocket. If the primer pocket is larger than a certain size, does that mean it's going to scorch the bolt face or it will be unable to hold a primer, or what?
 
gltaylor said:
Brownells sells go/no go gauges for primer pockets. Lg Rif/lg Pistol and Small /Rif, Sml/pistol.
They also indicate primer pocket depth. Easy-peasy one step check before you waste a primer on a ruined piece of brass.
I can take a photo if anyone is interested and post it.
Click to expand...
This business isn't hard, Throw your calipers in a pocket and spin the case to get an average reading of the pocket! Need to confirm further? Pin gauge it!
 
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