.243 blown primers

[myponga]

My mate has a .243 sako, and his load is 38.5grns of ar2209 with 100grn nosler partitions, and sdated 1.6mm off of the lands. The primers blow out.so he reduced the load to 37grns and the same thing happened. This is with Winchester primers,yet with federal primers its fine. Any one got any clues?

[rscott5028]

The question is whether it's due to the firing pin shape/protrusion or pressure.

If I'm not mistaken, Winchester primers tend to run hotter than Federal. And, Federal primers tend to be softer material and more sensitive.

If those are even true assumptions, then it would seem that he's hovering around MAX pressure with the Win primers.

The great thing about safe reloading practices is that it doesn't matter. You simply back down to a safe level and work up slowly whenever you change components and including using new powder lot numbers.

-- richard

[Broz]

Hole in the primer from the pin or completely blown out of the case?

Either one I say it is too hot of a load. But a sharp, or pin with a burr, could pierce a primer if you are just getting a pin hole.

Jeff

[davewilson]

a firing pin spring that's too weak can also cause this.

[myponga]

Thanks for the replies guys, yeah the primer is completly out of the primer pocketthis is a starting load for this powder, according to the adi handloaders guide.

[Broz]

Originally Posted by myponga

Thanks for the replies guys, yeah the primer is completly out of the primer pocketthis is a starting load for this powder, according to the adi handloaders guide.

Man, the only thing I have ever seen that done this was a very hot load. Like 5 gr to much. I would be for backing it off and checking velocity. Or maybe someone here could run it on "quick Load" for you.

So after fired and the primer is blown out,, I take it the pocket is swelled and will no longer hold a primer. That could only be very excesive pressure.

Jeff

[rscott5028]

Surely the scale has been calibrated and cross checked....