I recently fired some new 204 reloads, my first time loading them. I fired them from a Ruger #1 stainless with a heavy barrel. I didn't notice any signs of high pressure other than these primers looking a little flat. These links show some factory loaded ammo ( the brass primers ) and my reloads the silver primers ( CCI 400's )

They don't look all that bad to me but I've never had primers flatten out this much before.

http://www.777play.com/downloads/204/204-1.jpg
http://www.777play.com/downloads/204/204-2.jpg
http://www.777play.com/downloads/204/204-3.jpg
http://www.777play.com/downloads/204/204-4.jpg
http://www.777play.com/downloads/204/204-5.jpg

Thanks

The radius of the primer cup is still evident so I'd say these primers are not flattened to the point of indicating anything to me.

Thanks Cukrus

Be careful with CCI 400 primers and loads that approach maximum. The walls of the 400 primer are thinner than 450's and most others. I found this out while developing some loads and before I got to max I saw smoke in the receiver after a shot. The primer was pierced. I found that the primer was too thin for the .204. I switched to CCI BR4 and have not had any problems again. I wish the 400's had worked I bought 1000.

Those look normal to me.Cukrus has it right -- flattened primers will generally show no remaining edge radius, but will be flattened all the way across the primer pocket and, when removed from the case, will look like a little flat-topped mushroom.

Also keep in mind that the only thing you can positively say about flattened primers is that something flattened the primers. You can NOT automatically conclude what that something was, however.

When I first got mine it came with a few boxes of Hornady factor ammo. Those fired primers were flatter than that and the machine marks from the bolt face were visible.

Looks OK. Radius is still there. No sign the primer tried to crawl into the firing pin hole. Not a 100% guarantee that you aren't courting high pressure as some primers are stout. As long as you stay within your reloading manual's specs you are good to go with this load.
Expect you would get hard extraction along with flattened primers otherwise.

Thanks for the responses, I think Doctor Duck is on the right track with what I'm seeing. I wanted to get BR-4's but my reloading supplier was sold out so I just picked up a couple hundred 400's. I just think they are a little thin for this load. While shooting my 7mm I notice "some" flattening but I've never had them come out this flat before. As for the hard extractions, the ruger #1 doesn't seem to care what it's pulling out of the chamber it just comes flying out.