Not really getting primer cratering

[veep]

Hi all,

Doing my reading on reloading and the various safety concerns.

Can't say I'm really getting the primer cratering issue?

I get the problem of over pressure pushing back on the primer, but the picture or two that have been along with the articles just look like a regular firing ping strike on a regular primer?

To me anyway...

I'm obviously missing something but can't see what it is.

Educate a noob

[agentzero]

It can be very subtle. I guess people aren't going out of their way to work up dangerous loads so they can show examples of massive cratering

Search again, you will find pictures of what looks like a fine ring around the primer strike hole where the primer has pushed back into the firing pin hole in the bolt.

This is the start of what you're looking for.

[Muddy1967]

Educate a noob

This sounds like a new Forum Heading

[Supporter]

This sounds like a new Forum Heading

Ha ha. Totally should be.

[tucked]

I guess people aren't going out of their way to work up dangerous loads so they can show examples of massive cratering

Yeah, funny that

[on_one_wheel]

Using the primer for signs for pressure is the least reliable form of testing. You need to be mesauring for case head expansion with a micrometer right at the base of the case head above the extractor grove if you are serious abuot pushing the envlope. The process is well explained in Nick Harvey's reloading manual. Iv got 2 other reloading manuals and Nick's is by far the best. http://www.ebay.com.au/itm/Nick-Harvey- ... 232fb1a573

[veep]

You need to be measuring for case head expansion with a micrometer right at the base of the case head above the extractor grove if you are serious about pushing the envelope.

No, not looking to push the envelope. Just getting my head around things.

Cheers for the book reference though.

[Antie]

Good example here



You can clearly see in the 3rd one along where the primers pushed back into the firing pin hole.