Cratered primers ?

L

Lodgepole

New member
My Ruger American 223 has me confounded. I'm loading 24.5 gr of H335 with CCI 400 primers Behind Sierra 53 Gr HP match The Sierra manual says 27.6 gr is max and 24.1 is minimum. Im using winchester brass. Maybe I don't know what cratering looks like. It's not much of a crater but you can catch your fingernail on it .Suggestions welcome
 
Does it do it with factory ammunition? If so it's the firing pin is not filling the tunnel. Currently almost all new Remingtons do that now.

Greg
 
My buddy & I each have a TC Venture 22-250, that both do it.
Factory response was they error on the side of heavy fp strike vs light, and that it was normal.

These are factory rounds.
160766325.PmwH8v61.jpg

 
I have not shot any factory ammo in it GL. My craters are mole hills and yours are mtns compared to those Bob ! Bullet is not touching the rifling Old Cat.Maybe i could go back up to 26.5 gr and see what happens ? Thanks for the help
 
Originally Posted By: pahntr760I'm betting it is primer flow due to a slightly oversized FP hole. Cratered primers are not a very good indicator of pressure.

Yep
 
Notice how round the primer shoulders are in the pic above, that's good.
A too-hot round will flatten the shoulder and have a mushroom profile when looking from the side.
 
CCI 400's are soft primers, switch to 205's 450's, or rem 7'1/2's , keep the load the same and you will see what i am talking about, more than likely you will be able to up your charge of 335.
 
Cratered primers are probably the most over rated, misused indicator of over pressure. You'll see cratered primers in most fired ammunition. As previously mentioned, it's due to the softness of the cup and tolerance between the firing pin and pin hole.

If you use the primer condition as one of your indicators, look for flattening. That is the reduction of the cup radius. The more squarish looking, the higher the pressure.
 
here you go. type this in your search engine.it is at hodgon reloading. this will answer your questions. I always use this when I have a question. use a good starret micrometer. type in simple trick for montoring pressure of your rifle reloads.
 
cant help with the pressure signs.i also shoot 223 with h335 and use cci 450 primers. 400s was shooting horrible because i probably wasn't getting enough burn so someone said ball powders-mag primers and once I did this I can put 5 in a dime and I'm around 24gr of h335 and no signs of pressure.

I was having issues with primers not seating all the way and not going off so I loaded 4 empty cases with cci 400 and 450 primers and just shot the primed case with no powder or bullet and the primers cratered so you might not be getting enough burn. I seen something on another reloading sight THR saying that low pressure will also cause cratering.
 
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