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Primer Cratering
Mr. Gunz
Member Posts: 1,621 ✭✭✭
What causes it?
I'm getting minor primer cratering on my new loads, they are below max. and there is also cratering with factory loads...whats the deal?
I'm getting minor primer cratering on my new loads, they are below max. and there is also cratering with factory loads...whats the deal?
Comments
What do the craters look like? Are the edges of the primer flat? Any other unusual signs of pressure? If so, stop and get the rifle checked out. If not read below.
When it is both reloads and factory it might be a minor headspace problem. How is the accuracy with this rifle? Try a partial full sizing when you reload and see if the problem pops up again. To do this you just leave the shellholder a couple thousandths below the die instead of all the way up. You should see where the neck is resized to just above the shoulder junction. Then you shoulder should sit in the chamber all the way out where it was formed.
There is always the possibility too that it is the shape of the firing pin or the firing pin hole is too big and it gets too much of a hit on the primer. check those out while looking for other problems.
Those are just some ideas. -Good luck
below max in a saami chamber,...I am betting it is just normal cratering and not from pressure issues.
Keep in mind, pressure signs show up starting around 70,000psi. Once you see them, you are already a ways past max for your rifle.
mild primer cratering appears in most every rifle. The primers are rather soft, and under some 55,000psi will flow back around the firing pin at the instant of ignition before it returns into the bolt body. Now, if your primers are getting flat (looks as though they are filling out more of the primer pocket) and have a much more pronounced crater, then that is a sign or pressure.
below max in a saami chamber,...I am betting it is just normal cratering and not from pressure issues.
Keep in mind, pressure signs show up starting around 70,000psi. Once you see them, you are already a ways past max for your rifle.
Yeah I know i'm not past max, no sticky cases or any other signs, I think i'll just leave it how it is, and no i'm not flattening out the primers