Primer cratering

[Matt304]

I am using Remington 9-1/2 large rifle primers, and started working my loads up for maximums in a pistol. The primers started to flatten out on my final loads and primers are cratering a small amount around the firing pin dent. There are no other pressure signs.

I am wondering if magnum primers would be any thicker and help my problem, or if I am simply pushing it too far.

Thanks.

 

[wally]

If your gun doesn't do this with Remington factory ammo, I think you are pushing too far.

Magnum primers, while nomially "harder" will also raise pressures a bit.

--wally.

 

[Ol` Joe]

Rem 9 1/2 primers are likely heavier cupped then mag pistol primers. They are built to stand greater pressure then the pistol primers. I`d back off.

 

[Matt304]

I am shooting them from a 444 marlin, and the 330gr bullets are so long that the increasing brass thickness towards the base prevents them from chambering properly when seated all the way. So I am having to seat them out onto the lands about 20/1000s, and I think this may be causing the pressure to spike at these max loads. I am using 48.5gr of RL-7. I will back off like you guys say.